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5.3 - More on Experiments

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    I'm going to record
    from the current slide.
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    Sorry. Today we're going to
    be talking about Chapter 11.
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    More on experiments: confounding
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    and obscuring variables,
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    and there's a little girl
    hiding behind a tree,
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    and she is the third
    variable in your experiment.
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    You don't want her
    to be hiding and
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    explaining the results
    of your experiment.
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    Before I review with you,
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    I did want to go over some
    assignments that are due.
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    This week should be pretty
    light on assignments,
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    and that's because I
    want you to be working
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    on your method and
    your results section,
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    working on sprucing
    up your intro
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    if you have any comments.
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    This Sunday, we're going to
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    have the quiz on Chapter 11 due,
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    and then next Sunday is
    going to be pretty heavy.
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    I want your Pquiz on Chapter
    12 and your second draft,
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    which will include a
    revised introduction.
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    If you've got feedback from
    me, you can also schedule
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    an appointment with me if
    you want more feedback,
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    a method section, which
    we'll talk about today.
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    An anticipated results and
    data analysis section,
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    we'll also talk
    about that today,
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    and a discussion section.
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    We'll talk about that Wednesday
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    if we don't get to it today,
    the discussion section.
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    But by the end of this week,
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    you should have all of
    the things you need
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    to be able to write those
    sections of the paper.
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    Any questions? Alesia,
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    do you know what
    measures you're using
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    to measure introversion
    and extroversion?
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    I don't know the specific ones.
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    I was planning on looking
    them up today, actually.
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    Rick or Haley,
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    if you need help looking for
    those measures, let me know.
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    I'm more than happy to help you.
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    I've got enough
    experience to be able
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    to do it pretty quickly,
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    and I don't want you to waste
    a lot of time looking for
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    those measures. Sorry, Rick.
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    You should be using that
    time to write your papers,
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    because that's what I care
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    about more than actual measures.
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    We can always talk about
    the measures later.
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    Review questions.
    Are you all ready?
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    Me going to feel really
    bad about myself,
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    really good about myself,
    depending on how you do.
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    No pressure. What's an
    independent variable?
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    We're starting off pretty easy,
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    and then we're going to
    get a little harder.
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    It's the variable that
    gets manipulated.
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    Manipulated or measured
    by the experimenter.
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    Then the dependent
    variable is? Alesia.
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    What's the word?
    It's also measured,
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    but it's going to depend on
    the independent variable.
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    That's just how I remember them,
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    but it's what you're
    really looking for.
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    It's your outcome variable.
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    It's influenced by your
    independent variable.
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    Those are acceptable answers.
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    Ann, can you give
    me an example using
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    your research question? Haley.
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    Should I say my
    research question, too?
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    Sure.
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    My research question is,
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    how do age differences
    and being a woman in
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    a leadership position affect
    how they are viewed at work?
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    My IV, I actually have two.
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    The first one is age groups,
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    and that has an age group
    of 20-45 and then 45 plus,
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    and then the other independent
    variable is women in
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    leadership positions and men
    in leadership positions.
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    Then my dependent variable
    is how these women
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    are treated and viewed at work.
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    Just generally how people
    are treated at work, right?
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    Yeah.
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    Perfect. Great. Because all
    that makes sense so far.
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    That's an easy question.
    What's an experiment?
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    I know what an experiment is,
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    but I always have trouble
    putting it into words.
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    Just throw out some words
    that you're thinking of.
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    It's when you're trying to
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    understand the relationship
    of two variables
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    and you use an
    experiment to do so.
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    That's great. You use
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    an experiment to establish
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    a relationship between
    two variables,
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    but it is different
    from a correlation
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    because what do you
    say about X and Y?
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    X has to cause Y.
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    Yes. X has to cause Y.
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    It establishes causality.
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    What is one thing that
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    experimenters do to
    establish causality?
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    Temporal precedence.
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    Temporal precedence. Yes,
    this what I was looking for,
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    but it's another question
    on the next slide.
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    It's temporal precedence.
    Wait hold on,
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    not Haley. Rick or Alesia.
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    What came first?
    What caused what?
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    Exactly. What caused what?
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    X comes before Y, so
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    your independent variable caused
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    your dependent variable?
    Great. What else?
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    That's the difference
    between a correlation just
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    shows that they have something
    to do with each other.
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    Exactly. In a
    correlational study,
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    you don't know what came first.
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    Perfect. What else?
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    Alesia, you're spot on.
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    You just need a little bit more.
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    What else? We talked
    about the hat, remember?
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    Little frog hat.
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    It's random assignment
    to one of X conditions.
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    Alesia, you're not
    going to have random
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    assignment because
    you're already
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    placing people into conditions,
    pre existing groups.
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    Rick, you probably will
    have random assignment,
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    and Haley, you won't have
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    random assignment because
    you can't randomly
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    assign people to sex or gender.
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    But what is it about
    random assignment?
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    Actually, we'll come
    to that question soon.
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    Random assignment to
    one of X conditions,
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    and you measure
    dependent variables,
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    and you control for as
    many variables as you can.
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    Alesia, I think this is
    something you brought up,
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    or is this why they
    try to control
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    as many variables as
    you can in a room?
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    Yes, this is why
    because we want to
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    establish that X causes Y.
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    Great. Let's see this one.
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    This one's a little tricky.
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    Why have two or more levels
    of an independent variable?
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    Alesia, I used your example.
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    Why do we have extraversion and
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    introversion as the
    two levels of an IV?
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    Why can't we just
    do extraversion?
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    I guess you could
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    say you're not getting
    the question answered.
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    You're only looking
    at one aspect
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    of it rather than
    the whole picture.
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    Yes. It's basically
    for comparison.
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    You don't just want
    descriptives of extraversion,
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    but you want to
    see the comparison
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    between extraversion
    or introversion.
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    Rick, you want to see
    the differences between
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    pre-COVID and during
    COVID, and Haley,
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    you want to see the
    differences between
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    age group and sex,
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    and you want your study
    to show that x1 one
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    differs from x2 on y. Rick,
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    this would be that
    loneliness scores
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    differ pre-COVID
    versus during COVID.
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    This is one of the questions
    that Haley already answered.
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    What factors allow an experiment
    to make causal claims?
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    One is temporal precedence,
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    so X comes before Y.
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    The independent variable comes
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    before the dependent variable.
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    Thus, we can say the
    independent variable
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    caused the dependent variable.
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    What else? Is one thing
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    in common between
    correlation and experiments.
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    Covariance. Variance.
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    Yes. Covariance.
    What does that mean?
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    Is it just that there's a
    relationship between the two?
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    Perfect. Then we have
    temporal precedence,
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    which we already talked about,
    and what's the last one?
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    Internal validity.
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    Yes. What does that mean?
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    Is there a C variable
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    that is associated with
    the other two variables?
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    It's a little girl that's
    hiding behind the tree.
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    If there's a little girl
    hiding behind the tree,
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    does that mean that you
    have good internal validity
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    or poor internal validity?
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    Poor internal validity.
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    Yes. If there's another
    variable that's hiding
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    that might have caused changes
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    in your dependent variable,
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    that is low internal validity.
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    Damn, you guys are putting
    it together. This is good.
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    Is it making more
    sense now that I'm
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    putting it in the questions?
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    I'm not going to feel
    too good about myself,
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    so I didn't get
    through all of them.
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    You guys are doing a great job.
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    What's the difference in
    the following designs?
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    Between versus within subjects.
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    This we just learned
    last week, so it's okay.
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    It doesn't make sense.
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    At least feel like you have
    it on the tip of your tongue.
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    I want to say that the
    within subject design
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    has to do with more time
    because you're doing
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    the same type of
    experiment repeatedly,
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    whereas the between
    it's happening once,
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    and then you have all your data.
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    It's very close. Within,
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    what is the same?
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    The participants.
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    The participants are the same.
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    Yes. Haley, go ahead.
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    Well, so the within is where
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    there's only one group
    of participants,
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    and they're given all the levels
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    of the independent variable.
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    This would be, sorry.
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    No, go ahead.
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    It would be for
    Rick's study where
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    he collects 100 people at Wu,
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    and then he has them fill
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    out the survey on
    loneliness pre-COVID,
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    and then he has them
    fill out the survey
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    of loneliness during COVID.
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    He has them go
    through all levels
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    of the independent variable.
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    Then what about
    between subjects?
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    There's different
    groups of participants
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    placed into the different
    levels of the IV.
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    Yeah. Between subjects is when
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    you have them placed
    into different groups.
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    Rick's study would be
    one group is randomly
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    assigned to pre-COVID
    loneliness scale,
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    another group is assigned to
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    during COVID loneliness scale.
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    Does that make sense? Between
    means you're comparing
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    between people and within
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    means you're comparing
    within the individual.
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    You're exposing them to the
    same independent variable.
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    Between; people are randomly
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    assigned to one of conditions.
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    Within; people are exposed
    to all of the conditions.
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    For some of you like Alicia,
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    you can't randomly you can't
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    assign people to be extroverts
    and then you're like,
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    now pretend to be
    introvert or Haley,
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    you can't do that for
    your study, either.
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    You can't be like,
    imagine you are
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    a woman in her 30s in
    a leadership position.
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    Now you're going to pretend
    that you're a man in
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    his 40s in a leadership
    position. You can't do that.
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    Another thing within subjects
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    that we talk about is that we
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    deal with problems
    by counterbalancing.
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    Let me give you an example
    using Rick's study.
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    Let's say Rick decides
    that he wants all of
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    his participants to complete
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    the pre-COVID survey and
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    then complete the
    during COVID survey.
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    There might be an
    issue with that, why?
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    Maybe they see what's going on.
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    Maybe they see what's going on.
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    They're like, pre-COVID.
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    Now I'm going to
    base my responses
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    during COVID on what
    I responded earlier.
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    We deal with these problems
    by counterbalancing.
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    What does that mean? [LAUGHTER]
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    Isn't it where you change up
    the order of the conditions?
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    Exactly. Give me an
    example with Rick's study.
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    I just read about it.
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    For Participant 1,
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    you do pre-COVID and
    then do after COVID,
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    and then Participant 2,
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    you do the opposite,
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    you do post-COVID first,
    and then pre-COVID.
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    Perfect. That way
    you can eliminate
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    the order of the
    independent variables
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    as a reason for the change
    in the dependent variables.
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    Perfect. You guys got it.
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    You're putting it all together.
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    Here's that again.
    What's the difference
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    between random selection
    and random assignment?
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    What's the purpose of each?
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    Random selection is you're
    choosing the sample
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    that will best represent
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    the population
    you're looking at,
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    and the random assignment
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    is you're taking that sample and
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    you're assigning them
    specific conditions.
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    Perfect. That's great.
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    For random selection,
    the purpose is,
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    you want it to be
    representative of your sample,
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    and then random assignment,
    what's the purpose of it?
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    We talked about it earlier.
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    It's not covariance, it's
    not temporal precedence.
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    Internal validity?
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    Yes. It's internal validity.
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    But why?
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    I was at the Pepsi study,
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    like randomly assigning
    people to Pepsi or Coke.
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    I'm blinking, and I'm sorry.
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    No, that's okay.
    Anyone else want to.
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    But you did it perfectly.
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    You did less words than
    I did. [OVERLAPPING]
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    Keeps for one side
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    to be overloaded with all
    something and the other one.
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    They'd be offset so they
    wouldn't be represent. Sorry.
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    No, that's fine. Keep going.
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    One side would be,
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    all girls or something like
    that or all Coke drinkers or.
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    Yes.
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    With random assignment, what you
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    do is that you evenly distribute
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    any individual difference
    variables that
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    could account for differences
    in your dependent variable.
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    The individual
    difference variable
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    that we were talking about
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    was drinking Coke versus Pepsi.
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    Rick's hypothesis is that
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    people will experience
    more loneliness
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    during COVID than pre-COVID.
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    But we also know that
    Coke drinkers tend
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    to experience more
    loneliness than
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    Pepsi drinkers because
    Pepsi is better.
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    There would be low
    internal validity
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    if in the during
    COVID condition,
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    we had more coke drinkers
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    than in the pre-COVID condition
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    where we had more
    Pepsi drinkers.
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    That individual
    difference variable,
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    whether you like Coke or Pepsi,
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    could also affect your dependent
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    variable, which is loneliness.
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    You basically said
    this too, Rick.
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    You said something like gender.
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    That's another individual
    difference variable.
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    Maybe gender affects
    feelings of loneliness
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    or feelings of competence
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    or whatever a
    dependent variable is.
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    Okay.
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    Does that make sense?
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    Yes.
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    This was the hardest
    question, Alicia.
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    You just got it.
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    Now this is basically all
    we've learned until today.
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    All nine chapters or 10
    chapters that we've gone over.
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    Any questions here?
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    If I put the hat on the
    exam, will that help?
  • 17:33 - 17:38
    [LAUGHTER] I feel like
    it. Remember the hat.
  • 17:38 - 17:41
    Back to the girl that's hiding.
  • 17:41 - 17:45
    We're going to talk
    about experiments again,
  • 17:45 - 17:46
    but now we're going
    to talk about
  • 17:46 - 17:48
    confounding and
    obscuring variables.
  • 17:48 - 17:50
    It's going to be all
    about this little girl,
  • 17:50 - 17:51
    the third variable that could
  • 17:51 - 17:53
    affect the results
    of our studies.
  • 17:54 - 17:56
    I also just posted
    the PowerPoint,
  • 17:56 - 17:58
    if you want to go
    online and get it.
  • 17:58 - 18:00
    I was working on this
    until class time,
  • 18:00 - 18:02
    so if you're going to go and get
  • 18:02 - 18:04
    it and take some
    notes, that's cool.
  • 18:06 - 18:09
    For this chapter,
    we're going to talk
  • 18:09 - 18:11
    about threats to
    internal validity,
  • 18:11 - 18:15
    which we've already
    established as having
  • 18:15 - 18:16
    a third variable that might
  • 18:16 - 18:20
    account for changes in
    the dependent variable.
  • 18:20 - 18:21
    What we're really
    looking for is,
  • 18:21 - 18:23
    did the independent
    variable really
  • 18:23 - 18:26
    cause the difference in
    the dependent variable?
  • 18:26 - 18:29
    Then we'll also
    discuss null effects.
  • 18:29 - 18:31
    What if the independent variable
  • 18:31 - 18:32
    doesn't make a difference?
  • 18:32 - 18:33
    What if you find no difference
  • 18:33 - 18:34
    in your dependent variable?
  • 18:34 - 18:36
    Does that really mean that
  • 18:36 - 18:39
    your independent variable
    cause no difference,
  • 18:39 - 18:40
    or is there a lurking
    little girl that's
  • 18:40 - 18:41
    messing with your
    data that makes it
  • 18:41 - 18:44
    seem like there's no difference?
  • 18:45 - 18:49
    Within the threats to
    internal validity,
  • 18:49 - 18:51
    did the independent variable
    really cause the difference?
  • 18:51 - 18:54
    We have these four
    bullet points.
  • 18:54 - 18:58
    First, we're going to go over
    the really bad experiment.
  • 18:58 - 19:01
    We'll also talk
    about six potential
  • 19:01 - 19:03
    internal validity
    threats in one group,
  • 19:03 - 19:06
    three potential internal
    validity threats.
  • 19:07 - 19:09
    If there are so
    many threats, why
  • 19:09 - 19:10
    do we even conduct experiments?
  • 19:10 - 19:13
    Hopefully, I'll convince you
    that they are still useful.
  • 19:13 - 19:15
    The really bad experiment.
  • 19:15 - 19:17
    This is the experiment that
    I talked about with within
  • 19:17 - 19:20
    subjects design when we
    talked about brick study,
  • 19:20 - 19:22
    but Rick your
    experiment isn't bad.
  • 19:22 - 19:24
    I was just using it as a
    within subjects design.
  • 19:24 - 19:26
    You're doing between
    subjects design,
  • 19:26 - 19:28
    so this makes it better.
  • 19:28 - 19:32
    The three examples on
    this slide illustrate
  • 19:32 - 19:34
    what's known as a
    really bad experiment.
  • 19:34 - 19:37
    Diagram A is just
    a general diagram.
  • 19:37 - 19:39
    You have your participants,
  • 19:39 - 19:42
    you measure the dependent
    variable beforehand,
  • 19:42 - 19:44
    you give them the treatment,
  • 19:44 - 19:46
    and then you measure
    your dependent variable.
  • 19:46 - 19:48
    What you're looking
    at, is changes in
  • 19:48 - 19:52
    your dependent variable as
    a result of your treatment.
  • 19:52 - 19:59
    In experiment B, this is
    discussed in your textbook.
  • 19:59 - 20:03
    Niko, a summer camp counselor
    and psychology major
  • 20:03 - 20:06
    noticed that in a
    cabin of 15 boys,
  • 20:06 - 20:08
    that there is an
    especially rowdy bunch.
  • 20:08 - 20:10
    He's heard that a change
    in diet might help
  • 20:10 - 20:12
    calm them down,
    so he eliminates.
  • 20:12 - 20:14
    He measures rowdy
    behavior first,
  • 20:14 - 20:16
    so they have really
    rowdy behavior.
  • 20:16 - 20:17
    He reduces their sugar,
  • 20:17 - 20:20
    and then he measures their
    rowdy behavior again.
  • 20:20 - 20:24
    He reduces their sugar for
    two days, and as expected,
  • 20:24 - 20:26
    confirming his hypothesis,
  • 20:26 - 20:27
    when he reduces
    sugar for two days,
  • 20:27 - 20:30
    their rowdy behavior
    has decreased.
  • 20:30 - 20:32
    We'll talk about
    why that might not
  • 20:32 - 20:36
    be caused by the sugar.
  • 20:36 - 20:40
    In another study, they
    have 40 depressed women,
  • 20:40 - 20:42
    all of whom are
    interested in receiving
  • 20:42 - 20:44
    psychotherapy to treat
    their depression.
  • 20:44 - 20:47
    Dr. Yuki measures depression
  • 20:47 - 20:49
    before they start
    cognitive therapy.
  • 20:49 - 20:51
    Then they start
    cognitive therapy,
  • 20:51 - 20:53
    and at the end of the 12 weeks
  • 20:53 - 20:54
    session of cognitive therapy,
  • 20:54 - 20:59
    they measure depression again
    and finds that on average,
  • 20:59 - 21:01
    people's levels of
    depression have
  • 21:01 - 21:05
    decreased through what she's
  • 21:05 - 21:07
    assuming is through
    the cognitive therapy.
  • 21:08 - 21:11
    Can anyone tell me why
    these studies might not be
  • 21:11 - 21:16
    good before we get into it,
  • 21:16 - 21:18
    intuitively, before we get into
  • 21:18 - 21:20
    the actual terms for
    all these things.
  • 21:22 - 21:25
    I want to say you're
    assuming that
  • 21:25 - 21:29
    there's only one potential.
  • 21:33 - 21:35
    Yes.
  • 21:35 - 21:37
    Yeah, so one potential cause.
  • 21:37 - 21:39
    Let's go with this
    one, for instance.
  • 21:39 - 21:43
    Niko is assuming that because
    he reduced the sugar,
  • 21:43 - 21:46
    the boys are less rowdy.
  • 21:46 - 21:48
    But what's another explanation
  • 21:48 - 21:51
    for why they might
    be less rowdy?
  • 21:53 - 21:56
    Maybe they went on a
    long hike that day.
  • 21:56 - 21:58
    Yeah, maybe they went on
    a long hike that day.
  • 21:58 - 22:01
    Maybe they get tired
    of being rowdy.
  • 22:01 - 22:02
    You be rowdy for, like,
    three days and then
  • 22:02 - 22:04
    you're tired out.
    You're not as rowdy.
  • 22:04 - 22:06
    Great. Maybe there were
  • 22:06 - 22:09
    other activities.
    What's another thing?
  • 22:16 - 22:21
    Maybe time. Maybe this
    was when they first met,
  • 22:21 - 22:22
    and they're all
    trying to show each
  • 22:22 - 22:24
    other how rowdy they are,
  • 22:24 - 22:25
    and at the end, they're
    like, Okay, you
  • 22:25 - 22:26
    already know me. I don't care.
  • 22:26 - 22:28
    When you go on a
    first date, right,
  • 22:28 - 22:29
    you try to, like,
    be your best self,
  • 22:29 - 22:30
    and then after a while,
    you're like, Okay,
  • 22:30 - 22:34
    I can't keep this up,
    you're just normal.
  • 22:34 - 22:36
    Okay, what about this study?
  • 22:36 - 22:39
    For depression, they
    have cognitive therapy,
  • 22:39 - 22:41
    and then they decrease
    their depression.
  • 22:41 - 22:44
    Yeah, it could be due
    to cognitive therapy.
  • 22:44 - 22:48
    What's another
    potential explanation?
  • 22:49 - 22:52
    Like, seasonal factors, maybe?
  • 22:52 - 22:53
    That's a great explanation.
  • 22:53 - 22:56
    Yeah. Maybe Doctor Yuki
  • 22:56 - 22:58
    recruited people
    during the winter,
  • 22:58 - 23:00
    and all these women
    had depression.
  • 23:00 - 23:03
    Then she gives them
    cognitive therapy.
  • 23:03 - 23:05
    Look, it's spring.
  • 23:05 - 23:06
    They have less depression.
  • 23:06 - 23:08
    It might not be because
    of the cognitive therapy.
  • 23:08 - 23:10
    I might just be the
    change in season.
  • 23:10 - 23:14
    Perfect time. Anything else?
  • 23:16 - 23:18
    At events.
  • 23:18 - 23:21
    Life events. Perfect. Can
    you give us an example?
  • 23:21 - 23:25
    Like maybe at the beginning,
  • 23:25 - 23:27
    they just went through,
  • 23:27 - 23:28
    like, a really bad divorce,
  • 23:28 - 23:30
    and then after they were,
  • 23:30 - 23:32
    like, getting back
    on their feet.
  • 23:32 - 23:35
    Yeah. Maybe she recruited all
  • 23:35 - 23:38
    of these women as part
    of her practice, right?
  • 23:38 - 23:39
    Like, she knew that
  • 23:39 - 23:40
    these women were going
    through a divorce.
  • 23:40 - 23:42
    She's like, Okay, let
    me measure depressi
  • 23:42 - 23:43
    and then let me
    give you therapy,
  • 23:43 - 23:44
    and then we'll measure
    your depression again.
  • 23:44 - 23:47
    Maybe it was just
    time. Yeah, those
  • 23:47 - 23:49
    are all good explanations.
  • 23:49 - 23:50
    The reason why I have you go
  • 23:50 - 23:53
    through this painstakingly is
  • 23:53 - 23:55
    because I want you to be able to
  • 23:55 - 23:59
    work through it in case you
    forget something on the exam,
  • 23:59 - 24:00
    because all of the things
    that you've talked
  • 24:00 - 24:02
    about have actual terms to them,
  • 24:02 - 24:04
    which we'll talk about shortly.
  • 24:04 - 24:07
    Alright. This is known as the
    one-group posttest design.
  • 24:07 - 24:10
    So this is a graphical
    representation of the changes.
  • 24:10 - 24:13
    On the Y axis, we
    have rowdy behavior.
  • 24:13 - 24:14
    This for the campers.
  • 24:14 - 24:15
    Beginning of the week, they have
  • 24:15 - 24:16
    this much rowdy behavior,
  • 24:16 - 24:19
    about 70% rowdy behavior.
  • 24:19 - 24:20
    At the end of the week,
  • 24:20 - 24:22
    after the sugar-free diet,
  • 24:22 - 24:26
    they have about 43%
    rowdy behavior.
  • 24:26 - 24:28
    Whoa, it's a huge decrease.
  • 24:28 - 24:30
    What about depression?
    Pre-therapy,
  • 24:30 - 24:33
    these women had a score
    of 17 in depression,
  • 24:33 - 24:35
    but after therapy, they
  • 24:35 - 24:37
    experienced a score of
    about ten in depression.
  • 24:37 - 24:40
    Let's make sure all
    the college campers
  • 24:40 - 24:41
    eat a sugar-free diet,
  • 24:41 - 24:43
    and let's make sure
    that women who are
  • 24:43 - 24:46
    depressed all get
    cognitive therapy.
  • 24:46 - 24:48
    Is that a good assumption
    to make from that?
  • 24:48 - 24:52
    No, not necessarily.
  • 24:52 - 24:54
    Okay, so let's talk about
  • 24:54 - 24:55
    the internal validity threats
  • 24:55 - 24:58
    in one-group
    pretest-posttest designs.
  • 24:58 - 25:00
    These are some of the examples
    that you came up with,
  • 25:00 - 25:02
    but these are the terms
  • 25:02 - 25:05
    that go along with
    those examples.
  • 25:05 - 25:08
    We'll talk about
    maturation threats.
  • 25:08 - 25:10
    What does maturation sound like?
  • 25:13 - 25:16
    Terry mature.
  • 25:16 - 25:18
    Yeah. What does
    mature sound like?
  • 25:18 - 25:21
    Like, what does it mean?
  • 25:25 - 25:28
    Like overtime.
  • 25:28 - 25:31
    I think that's what we
    talked about getting
  • 25:31 - 25:33
    tired out. It got hold.
  • 25:33 - 25:36
    Yes, that's why I had
  • 25:36 - 25:38
    to go through that exercise
    so that we could then talk.
  • 25:38 - 25:40
    I'm going to go over what
    these mean, obviously,
  • 25:40 - 25:41
    but I just wanted to,
  • 25:41 - 25:43
    like, get your
    intuition working.
  • 25:43 - 25:46
    History threats, regression
    threats, attrition threats,
  • 25:46 - 25:48
    testing threats and
    intimidation threats
  • 25:48 - 25:50
    , and combined threats.
  • 25:50 - 25:52
    We're just talking about
    all the threats today.
  • 25:52 - 25:55
    Okay, maturation threats.
  • 25:55 - 25:57
    A change in behavior that
  • 25:57 - 26:01
    merges spontaneously. Over time.
  • 26:01 - 26:03
    For example, children
    become better and faster at
  • 26:03 - 26:05
    solving addition and
    subtraction problems
  • 26:05 - 26:06
    as they get older,
  • 26:06 - 26:08
    trees grow taller with
    age, and over time,
  • 26:08 - 26:10
    people tend to recover on their
  • 26:10 - 26:13
    own from various
    psychological disorders.
  • 26:13 - 26:18
    This is the original graph
    that we had, or sorry, yeah,
  • 26:18 - 26:20
    the original graph
    that we had with
  • 26:20 - 26:23
    this line showing us that women
  • 26:23 - 26:25
    in the therapy condition
  • 26:25 - 26:29
    decreased in depression
    across time, right?
  • 26:29 - 26:31
    Women in the pre-therapy
    condition experience
  • 26:31 - 26:34
    more depression than women in
    the post-therapy condition.
  • 26:34 - 26:37
    But we don't have a
    full comparison group.
  • 26:37 - 26:38
    This is what Alesia was saying.
  • 26:38 - 26:40
    We don't have something
    to compare it to.
  • 26:40 - 26:43
    What if we had a
    no-therapy group,
  • 26:43 - 26:46
    a group that actually
    didn't receive any therapy,
  • 26:46 - 26:49
    and we see how they
    change across time.
  • 26:49 - 26:53
    If the no therapy comparison
    groups' depression level
  • 26:53 - 26:54
    decreased across time,
  • 26:54 - 26:57
    this suggests that it's
    a maturation effect,
  • 26:57 - 26:59
    it's a maturation effect and not
  • 26:59 - 27:02
    necessarily that it's
    the therapy effect.
  • 27:02 - 27:06
    But because we do have
    that comparison line now,
  • 27:06 - 27:08
    which one seems like it
    decreased more over time?
  • 27:08 - 27:10
    Their depression
    decreased more over
  • 27:10 - 27:15
    time. Which one
    does it seem like?
  • 27:15 - 27:17
    The therapy group.
  • 27:17 - 27:20
    Yeah. Because the therapy group,
  • 27:20 - 27:23
    their depression decreased
    even more significantly over
  • 27:23 - 27:26
    time relative to the no therapy
    group, then we can say,
  • 27:26 - 27:30
    Okay, it might be the
    therapy that's causing
  • 27:30 - 27:31
    this decrease in depression
  • 27:31 - 27:34
    and not necessarily maturation.
  • 27:35 - 27:39
    Does that make sense? If they
  • 27:39 - 27:40
    wouldn't have received therapy,
  • 27:40 - 27:41
    they would have
    still decreased in
  • 27:41 - 27:43
    depression quite a bit,
  • 27:43 - 27:45
    but it wouldn't have
    been as significant as
  • 27:45 - 27:52
    including therapy on top
    of just simple maturation.
  • 27:52 - 27:56
    The way that you prevent
    maturation threats
  • 27:56 - 28:00
    is to try to have
    comparison groups.
  • 28:00 - 28:01
    In a really bad experiment,
  • 28:01 - 28:04
    you don't have a
    comparison group,
  • 28:04 - 28:05
    but in a true experiment, there
  • 28:05 - 28:07
    should be a comparison group.
  • 28:07 - 28:11
    Okay. If you wanted to say what
  • 28:11 - 28:13
    the true effect of therapy would
  • 28:13 - 28:15
    be on decreased depression,
  • 28:15 - 28:19
    you would subtract the effect
    of just simple maturation.
  • 28:19 - 28:21
    It decreases about four points
  • 28:21 - 28:25
    from the total
    effect of therapy.
  • 28:25 - 28:29
    It decreases about six points.
  • 28:29 - 28:32
    In reality, therapy only
    helps about two points
  • 28:32 - 28:36
    above what simple
    time would give you.
  • 28:36 - 28:39
    Does that make sense?
  • 28:39 - 28:44
    Two, six or actually
    four points.
  • 28:44 - 28:47
    This is 18, and then
    it goes to, like, 16,
  • 28:47 - 28:51
    that's a decrease of
    two points, 18-12.
  • 28:51 - 28:53
    It's a decrease of six points.
  • 28:53 - 28:56
    6-2 is about four.
  • 28:56 - 28:58
    The unique contribution
    of therapy
  • 28:58 - 29:02
    is a decrease in four
    points of depression.
  • 29:02 - 29:07
    Okay. Does that make sense? Ylo,
  • 29:07 - 29:09
    looking confused, Rick,
    does that make sense?
  • 29:10 - 29:13
    That part totally
    makes sense again.
  • 29:13 - 29:15
    I'm going, Oh.
  • 29:15 - 29:18
    Where did the numbers come from?
  • 29:18 - 29:21
    Oh, well, it's just the
    numbers that are here.
  • 29:21 - 29:24
    I'm just looking like,
    18 is this point.
  • 29:24 - 29:26
    Then this point is like 16.
  • 29:26 - 29:30
    I don't know how to read them.
  • 29:30 - 29:32
    I just don't know why
  • 29:32 - 29:34
    18 is there and not 57
    under or something.
  • 29:34 - 29:36
    Oh, the numbers are
    just arbitrary.
  • 29:36 - 29:39
    I'm just using the numbers
    that are on the graph.
  • 29:39 - 29:43
    But if you had this, you
    could say, and this graph,
  • 29:43 - 29:47
    you could say the unique
    effect of therapy was about
  • 29:47 - 29:48
    a four-point drop in
  • 29:48 - 29:52
    depression or whatever
    the actual scale was.
  • 29:52 - 29:56
    Okay. Any other
    questions or comments?
  • 29:56 - 29:58
    That's what I miss
    about being in class
  • 29:58 - 30:01
    is seeing people's faces,
    some people get it,
  • 30:01 - 30:02
    and then a lot of people don't,
  • 30:02 - 30:05
    so I like looking
    at faces. But okay.
  • 30:05 - 30:08
    History threats to
    internal validity.
  • 30:08 - 30:11
    What is a history threat?
  • 30:11 - 30:14
    This results when some
    external or historical event
  • 30:14 - 30:16
    affects most members of
  • 30:16 - 30:19
    the treatment group at the
    same time as treatment.
  • 30:19 - 30:21
    It's unclear whether the change
  • 30:21 - 30:22
    in the dependent variable for
  • 30:22 - 30:23
    the experimental group
    was the result of
  • 30:23 - 30:26
    the treatment or of
    the historical factor.
  • 30:26 - 30:30
    This is more about,
    like an actual event.
  • 30:30 - 30:34
    An example is, suppose you
    were studying the effects
  • 30:34 - 30:36
    of meditation on stress levels
    among college students,
  • 30:36 - 30:38
    and while you were
    conducting the study,
  • 30:38 - 30:41
    a violent event occurred
    on the college campus.
  • 30:41 - 30:42
    The meditation
    group did not show
  • 30:42 - 30:45
    significant decreases
    in stress levels,
  • 30:45 - 30:47
    but was that because the
    treatment wasn't effective?
  • 30:47 - 30:49
    It might not be, right?
  • 30:49 - 30:50
    Because you had this
    really stressful event
  • 30:50 - 30:52
    happen on campus.
  • 30:52 - 30:55
    Maybe the meditation
    was effective,
  • 30:55 - 30:58
    but the campus violence raised
    people's stress levels.
  • 30:58 - 31:04
    Alright, this is another study
  • 31:04 - 31:08
    that was discussed in your
    textbook in a college,
  • 31:08 - 31:10
    they had a go green campaign
  • 31:10 - 31:12
    where they emailed
    college students
  • 31:12 - 31:13
    starting in September,
  • 31:13 - 31:15
    and they told them
    to try to unplug
  • 31:15 - 31:17
    things that weren't
    being used and to turn
  • 31:17 - 31:18
    off the lights whenever
    they weren't in
  • 31:18 - 31:20
    a room to decrease
  • 31:20 - 31:23
    the number of kilowatt hours
    that were being used, right?
  • 31:23 - 31:24
    To go green.
  • 31:24 - 31:29
    What they found the Go
    green campaign in October.
  • 31:29 - 31:34
    This is the number of kilowatt
    hours change across time.
  • 31:34 - 31:37
    The people who got
    the emails decreased
  • 31:37 - 31:42
    their kilowatt hours from
    September to November.
  • 31:42 - 31:46
    But what about the no campaign?
  • 31:46 - 31:48
    These people didn't
    even receive an email.
  • 31:48 - 31:50
    They also decreased
    in the kilowatt hours
  • 31:50 - 31:54
    used between September
    and November.
  • 31:54 - 31:56
    It's a historical factor
    that could have happened
  • 31:56 - 31:59
    between September and
    November that might have
  • 31:59 - 32:02
    reduced their energy usage.
  • 32:05 - 32:08
    I want to say Halloween,
  • 32:08 - 32:08
    but I don't know if that's
  • 32:08 - 32:10
    gonna have anything
    to do with it.
  • 32:10 - 32:13
    Yes, maybe Halloween, and
    they're all going to parties,
  • 32:13 - 32:14
    so it's warm so they don't have
  • 32:14 - 32:16
    to use as much electricity.
  • 32:16 - 32:18
    But really, it's like in,
  • 32:18 - 32:20
    let's pretend that they're
    in North Carolina.
  • 32:20 - 32:23
    You probably use your air
    conditioner a lot less
  • 32:23 - 32:26
    between September and November.
  • 32:26 - 32:28
    Because both of
    the groups seem to
  • 32:28 - 32:33
    track along the same trend line,
  • 32:33 - 32:35
    then it shows that the campaign
  • 32:35 - 32:36
    wasn't actually effective.
  • 32:36 - 32:38
    It was just a history threat.
  • 32:38 - 32:42
    They all went through the
    same seasonal change.
  • 32:42 - 32:48
    However, if we find that in
    the beginning of September,
  • 32:48 - 32:50
    both the people that weren't
  • 32:50 - 32:51
    in the campaign and
    those who received
  • 32:51 - 32:55
    the email use the same
    amount of energy.
  • 32:55 - 32:57
    But at the end of the campaign,
  • 32:57 - 32:58
    the people who
    received the email use
  • 32:58 - 33:00
    significantly less energy than
  • 33:00 - 33:03
    those in the no
    campaign condition,
  • 33:03 - 33:06
    then we can say that
    the manipulation,
  • 33:06 - 33:08
    so whether they got
    the email or not,
  • 33:08 - 33:13
    actually reduced their level
    of kilowatt hours used.
  • 33:13 - 33:16
    Does that make sense? This is
  • 33:16 - 33:18
    an example of a
    history threat that
  • 33:18 - 33:20
    affects your dependent variable.
  • 33:20 - 33:22
    This is an example.
  • 33:22 - 33:24
    Same history threat
    is available,
  • 33:24 - 33:27
    but despite the same
    history being available,
  • 33:27 - 33:29
    there is still a difference.
  • 33:29 - 33:34
    Does that make sense?
    The green campaign
  • 33:34 - 33:36
    changed the level of
  • 33:36 - 33:39
    energy use greater than
    that which we would
  • 33:39 - 33:43
    normally see based
    on seasonal changes.
  • 33:52 - 33:56
    How do you avoid
    a history threat?
  • 33:56 - 33:58
    You can't always avoid
    a history threat,
  • 33:58 - 34:00
    but because you can't say, Well,
  • 34:00 - 34:03
    I don't want winter to happen.
  • 34:03 - 34:06
    You should measure
    a control group,
  • 34:06 - 34:08
    so a group that
    doesn't experience
  • 34:08 - 34:11
    any of the manipulation.
  • 34:11 - 34:14
    Something that happened
    at UC Santa Barbara,
  • 34:14 - 34:15
    when I was a student,
  • 34:15 - 34:18
    they were looking at one of
    my friends is a researcher
  • 34:18 - 34:22
    on romantic and also,
    platonic relationships.
  • 34:22 - 34:25
    Between friends and how
    close they feel to them,
  • 34:25 - 34:29
    they were also investigating
    how stressful events could
  • 34:29 - 34:32
    influence the closeness
    that you feel
  • 34:32 - 34:34
    to your friends and to
    your significant others.
  • 34:34 - 34:37
    They started collecting data,
  • 34:37 - 34:39
    I think in the fall, and
    they were collecting
  • 34:39 - 34:41
    it the entire academic year.
  • 34:41 - 34:44
    Then in May, we had the
    shooting that happened.
  • 34:44 - 34:46
    Then because they were
  • 34:46 - 34:48
    collecting that data
    for the entire year,
  • 34:48 - 34:52
    they had an entire year's
    worth of data pre shooting,
  • 34:52 - 34:54
    and then they had
    data post shooting.
  • 34:54 - 34:55
    Their research question actually
  • 34:55 - 34:58
    changed because of
    that historical event.
  • 34:58 - 35:02
    Sometimes because of things
    that happen in the world,
  • 35:02 - 35:06
    that might affect your
    research question
  • 35:06 - 35:10
    or what you're actually
    looking for in your data.
  • 35:10 - 35:13
    Does that make sense?
    Or like COVID,
  • 35:13 - 35:14
    there were researchers
    that were probably
  • 35:14 - 35:16
    collecting data on loneliness,
  • 35:16 - 35:19
    and then COVID hit and
    they're like, Oh, my God.
  • 35:19 - 35:21
    Jackpot.
  • 35:21 - 35:23
    This sucks, but Jackpot.
  • 35:23 - 35:25
    Basically. This sucks, but
    Jackpot because no one
  • 35:25 - 35:30
    else had data before
    COVID on this.
  • 35:30 - 35:36
    It sucks, yes, Jackpot
    sum. Does that make sense?
  • 35:36 - 35:40
    I think the message is just
    collect data all the time
  • 35:40 - 35:41
    because you never
    know what messed
  • 35:41 - 35:43
    up stuff is going to
    happen in the world.
  • 35:43 - 35:46
    What about regression threats?
  • 35:46 - 35:47
    What's a regression threat?
  • 35:47 - 35:52
    Regression means to return to.
  • 35:53 - 35:55
    This is also known
    as regression to
  • 35:55 - 35:58
    the mean or regression
    to the average.
  • 35:58 - 36:01
    This is a statistical concept in
  • 36:01 - 36:03
    which extremely low or
    extremely high okay,
  • 36:03 - 36:06
    extremely low or extremely
    high performance at time one
  • 36:06 - 36:09
    is likely to be less
    extreme at time two.
  • 36:09 - 36:12
    Closer to the average.
  • 36:12 - 36:16
    If you're in a really good
    mood or a really bad mood,
  • 36:16 - 36:18
    you'll probably be in
    a more moderate mood
  • 36:18 - 36:21
    tomorrow due to aggression
    because that's your average.
  • 36:21 - 36:23
    I was always scared of this,
  • 36:23 - 36:26
    and I'll 'cause I
    always got good grades.
  • 36:26 - 36:28
    I was like, oh, my God, there's
    gonna be a regression to
  • 36:28 - 36:30
    the mean because this can't
    be my real performance.
  • 36:30 - 36:32
    I'm going to have to get a
    fail to get the average of
  • 36:32 - 36:36
    a [inaudible] this is so you
    can remember it in that way.
  • 36:36 - 36:38
    Regression. If you
    perform really high,
  • 36:38 - 36:42
    then if that's not your
    true level of performance,
  • 36:42 - 36:45
    you can always dip down and
    go back to your average.
  • 36:45 - 36:47
    It's hard to tell with
    your own performance,
  • 36:47 - 36:50
    what, your true high
    or your true low is.
  • 36:50 - 36:52
    But if you have
    impostor syndrome,
  • 36:52 - 36:54
    then you're likely to think
    that your high performance is
  • 36:54 - 36:57
    not really your performance.
  • 36:57 - 36:59
    Hopefully, it helps
    you remember.
  • 36:59 - 37:02
    Regression and
    internal validity.
  • 37:02 - 37:04
    Regression threats only occur in
  • 37:04 - 37:06
    pre test post test designs.
  • 37:06 - 37:09
    Specifically, they only
    occur when a group has
  • 37:09 - 37:11
    an extreme pretest
    score high or low.
  • 37:11 - 37:13
    You can anticipate
    that the scores of
  • 37:13 - 37:14
    those participants will regress
  • 37:14 - 37:16
    towards the mean at post test.
  • 37:16 - 37:18
    One example of the
  • 37:18 - 37:21
    regression threat
    that we talked about,
  • 37:21 - 37:22
    of course, will be
    the depression score,
  • 37:22 - 37:24
    which we'll talk about
    these graphs shortly.
  • 37:24 - 37:33
    But another one is the
    campers with rowdy behavior.
  • 37:33 - 37:34
    Maybe they scored really,
  • 37:34 - 37:36
    really high on rowdy behavior,
  • 37:36 - 37:37
    but that's an extreme score.
  • 37:37 - 37:39
    They had to go back
    to their meme.
  • 37:39 - 37:42
    Their average rowdy behavior
    is probably not really high,
  • 37:42 - 37:43
    so they would expend a lot of
  • 37:43 - 37:47
    energy. Does that make sense?
  • 37:47 - 37:48
    Can you give me
    another example of
  • 37:48 - 37:51
    regression to the meme?
  • 37:51 - 37:55
    Brick's like, no,
    don't pick on me.
  • 37:55 - 37:58
    Alsia or Haley.
  • 38:00 - 38:08
    Would it be like like
    basketball players doing,
  • 38:08 - 38:11
    like, really, really
    well right before
  • 38:11 - 38:15
    their big NBA game of
    the year, whatever.
  • 38:15 - 38:18
    I don't know the terms. But then
  • 38:18 - 38:21
    that's not normally
    how good they perform.
  • 38:21 - 38:22
    They're just trying to get into
  • 38:22 - 38:24
    the final game or whatever.
  • 38:24 - 38:30
    Then they regress back to
    their mean after the big game.
  • 38:31 - 38:38
    Yes. We all have sort of a
    set baseline of our behavior.
  • 38:38 - 38:39
    How talkative we are in class.
  • 38:39 - 38:42
    Alsia do you talk this
    much in other classes?
  • 38:42 - 38:44
    I know.
  • 38:44 - 38:47
    No. Because this is, like,
  • 38:47 - 38:50
    a high level of
    talking in classes,
  • 38:50 - 38:52
    you probably regress
    to the mean in
  • 38:52 - 38:54
    your other classes and
    don't talk at all.
  • 38:54 - 38:57
    Is that true? Exactly, yeah.
  • 38:57 - 39:01
    That's true for me, too,
    because I am an introvert.
  • 39:01 - 39:04
    On Mondays and Wednesdays
    when I teach this class,
  • 39:04 - 39:05
    and when I teach
    the other classes,
  • 39:05 - 39:07
    I'm talking a lot and
    a lot and a lot for
  • 39:07 - 39:10
    like an hour and a
    half to four hours.
  • 39:10 - 39:12
    After I'm done teaching,
  • 39:12 - 39:14
    I just go in the living room
    and I turn off the lights,
  • 39:14 - 39:16
    and my boyfriend knows
    not to bother me
  • 39:16 - 39:18
    because I regress to
    the mean and I have to,
  • 39:18 - 39:19
    like, power back up.
  • 39:19 - 39:22
    Does that make sense? Is this
  • 39:22 - 39:24
    a better example of
    regression to me?
  • 39:24 - 39:25
    Brick, do you have an
    experience in your life?
  • 39:25 - 39:27
    Well, that's in a way,
  • 39:27 - 39:31
    to me, I'm relating to that.
  • 39:31 - 39:36
    After two hours of
    focusing on the class,
  • 39:36 - 39:39
    that's why I got to
    regress to my mean
  • 39:39 - 39:43
    of calm and take a walk
    to counterbalance.
  • 39:43 - 39:45
    Yeah, it makes sense.
  • 39:45 - 39:46
    You need to reset.
  • 39:46 - 39:48
    I just want you to
    think of those examples
  • 39:48 - 39:50
    in case it comes up on the exam.
  • 39:51 - 39:55
    How can you prevent
    regression to the meme?
  • 39:55 - 39:58
    You look at comparison groups
    and inspect the results.
  • 39:58 - 40:00
    If you look at the top graph,
  • 40:00 - 40:02
    you can see that both groups
  • 40:02 - 40:04
    have a similar level of
    depression at pre test,
  • 40:04 - 40:06
    but the therapy group
    had lower levels
  • 40:06 - 40:08
    of depression at post test.
  • 40:08 - 40:12
    Regression can be
    ruled out so here,
  • 40:12 - 40:14
    it's telling us
    that pre therapy,
  • 40:14 - 40:16
    the no therapy and
    the therapy group
  • 40:16 - 40:18
    had similar levels
    of depression.
  • 40:18 - 40:21
    But after receiving therapy,
  • 40:21 - 40:23
    the therapy group decreased into
  • 40:23 - 40:26
    depression more than
    the no therapy group.
  • 40:26 - 40:29
    If it was truly a
    regression to the mean,
  • 40:29 - 40:32
    it would look
    something like this.
  • 40:32 - 40:34
    Let's talk about this one.
  • 40:34 - 40:37
    In the pre therapy group, Sorry.
  • 40:37 - 40:41
    In the pre therapy
    condition or time,
  • 40:41 - 40:43
    the therapy group
    had higher levels of
  • 40:43 - 40:46
    depression relative to
    the no therapy group.
  • 40:46 - 40:48
    But after receiving therapy
  • 40:48 - 40:50
    or in that time
    period of time, too,
  • 40:50 - 40:52
    what they found is that
  • 40:52 - 40:54
    the no therapy group didn't
    change in depression,
  • 40:54 - 40:58
    whereas the therapy group
    did decrease in depression.
  • 40:58 - 41:00
    This shows us an example
    of regression to
  • 41:00 - 41:02
    the mean because in pre therapy,
  • 41:02 - 41:05
    the therapy group scored
    really high on depression,
  • 41:05 - 41:07
    and then post therapy,
  • 41:07 - 41:09
    they scored much lower,
  • 41:09 - 41:12
    whereas there were no changes
    in the no therapy group.
  • 41:12 - 41:15
    There's regression
    because they start off on
  • 41:15 - 41:20
    a more extreme score and
    then change after time.
  • 41:20 - 41:26
    Does that make sense in
    terms of regression? Brick.
  • 41:26 - 41:30
    But that's the middle one,
  • 41:30 - 41:32
    the one we were
    just talking about.
  • 41:32 - 41:34
    That's like what you want.
  • 41:34 - 41:36
    That reads right.
  • 41:36 - 41:40
    That's not necessarily
    what you want.
  • 41:40 - 41:44
    Because this is telling us that
  • 41:44 - 41:47
    these people might have
  • 41:47 - 41:49
    changed just because they
  • 41:49 - 41:50
    were very extreme
    in the beginning.
  • 41:50 - 41:53
    It could be what we want,
  • 41:53 - 41:55
    but it doesn't rule out
    regression to the mean as
  • 41:55 - 42:00
    a potential cause because
  • 42:00 - 42:02
    they were very extreme
    in the beginning.
  • 42:05 - 42:07
    Okay.
  • 42:07 - 42:09
    Does that make a
    little bit of sense?
  • 42:09 - 42:11
    This could be potentially
    what we want,
  • 42:11 - 42:13
    but we can't rule out regression
  • 42:13 - 42:15
    because of the extreme scores.
  • 42:15 - 42:18
    What about C?
  • 42:18 - 42:22
    The bottom graph depicts the
    therapy group starting out
  • 42:22 - 42:24
    at a higher level of
  • 42:24 - 42:26
    depression than the
    no therapy group,
  • 42:26 - 42:29
    but this pattern is
    reversed at post-test.
  • 42:29 - 42:32
    This is reversed at post-test
  • 42:32 - 42:33
    when no therapy group had
  • 42:33 - 42:35
    higher depression scores
    than the therapy group.
  • 42:35 - 42:39
    This couldn't be accounted
    for by regression alone.
  • 42:39 - 42:40
    Therefore,
  • 42:40 - 42:43
    the independent variable
    must have had an effect.
  • 42:43 - 42:45
    Because we have this
    crossover effect,
  • 42:45 - 42:47
    this is basically what's telling
  • 42:47 - 42:49
    us what the average should be.
  • 42:49 - 42:52
    This is what the average
    should be for typical people.
  • 42:52 - 42:55
    That average, it should
    be for typical people
  • 42:55 - 42:58
    isn't really different than
    the treatment condition,
  • 42:58 - 43:00
    then it's telling us that
    there might be issues.
  • 43:00 - 43:02
    In this case, because
    there is an extreme score,
  • 43:02 - 43:05
    it's telling us that
    regression might be an issue.
  • 43:05 - 43:09
    But here, because they were
    extreme to begin with,
  • 43:09 - 43:11
    and then they went extremely low
  • 43:11 - 43:14
    afterwards or eliminating
    any regression.
  • 43:14 - 43:15
    We're saying that people are
  • 43:15 - 43:16
    really depressed to begin with,
  • 43:16 - 43:19
    and they got much better
    than they would be expected
  • 43:19 - 43:23
    to if they were in the
    no treatment condition.
  • 43:23 - 43:30
    Does that make sense? Rick,
  • 43:30 - 43:33
    if it doesn't can
    explain it another way.
  • 43:33 - 43:37
    Well, it makes sense
    when you said when
  • 43:37 - 43:39
    that straight horizontal line
  • 43:39 - 43:42
    is a no treatment condition.
  • 43:42 - 43:45
    I guess, put like
    that, it makes sense.
  • 43:45 - 43:47
    I just thought it was like an
  • 43:47 - 43:50
    average condition or something.
  • 43:50 - 43:51
    No, it's a no treatment group.
  • 43:51 - 43:53
    It's like what would happen if
  • 43:53 - 43:54
    these people just didn't
  • 43:54 - 43:56
    receive any treatment
    across time?
  • 43:56 - 43:58
    What would happen naturally?
  • 43:59 - 44:04
    Alycia, does that
    make sense? Lily?
  • 44:04 - 44:06
    It does.
  • 44:06 - 44:10
    How does it affect
    internal validity?
  • 44:10 - 44:13
    There's another
    factor that could
  • 44:13 - 44:16
    account for the results in
    your dependent variable,
  • 44:16 - 44:18
    and how can they be
    prevented by having
  • 44:18 - 44:22
    a control group they
    can compare to?
  • 44:23 - 44:25
    What about attrition threats?
  • 44:25 - 44:27
    We have a lot of these.
  • 44:27 - 44:28
    This is another dataset
  • 44:28 - 44:30
    where we actually
    collected data from
  • 44:30 - 44:34
    freshmen to seniors
    at UC Santa Barbara.
  • 44:34 - 44:36
    Attrition, does anyone know
  • 44:36 - 44:38
    what the word attrition means?
  • 44:38 - 44:40
    It's okay if you don't.
  • 44:40 - 44:43
    I think I only know because
    it's in psychology.
  • 44:43 - 44:46
    This is a reduction.
  • 44:46 - 44:48
    It just means reduction,
    but in this case,
  • 44:48 - 44:50
    it means a reduction
    in participant numbers
  • 44:50 - 44:53
    from pre-test to post-test.
  • 44:53 - 44:57
    Attrition is only problematic
    when it is systematic.
  • 44:57 - 45:00
    In the top graph, two
    people drop out of
  • 45:00 - 45:05
    the study from
    pre-test to post-test,
  • 45:05 - 45:07
    and those students or
    those people who dropped
  • 45:07 - 45:10
    out scored really
    high on Time 1.
  • 45:10 - 45:15
    That might be an
    attrition threat.
  • 45:15 - 45:18
    This decreases the post-test
    mean dramatically.
  • 45:18 - 45:20
    You don't know whether
    it was the attrition.
  • 45:20 - 45:23
    These two people leaving or
  • 45:23 - 45:25
    the fact that they
    scored really high on
  • 45:25 - 45:27
    it that led to the change in
  • 45:27 - 45:31
    the dependent variable,
    which is the score.
  • 45:31 - 45:36
    In the bottom graph, attrition
    isn't really a factor
  • 45:36 - 45:37
    because people who drop out have
  • 45:37 - 45:40
    scores that are closer
    to the average.
  • 45:40 - 45:44
    If they drop out, the average
    doesn't really change.
  • 45:44 - 45:47
    Therefore, the attrition
    isn't a threat.
  • 45:47 - 45:50
    Another way to think
    about it is right
  • 45:50 - 45:53
    now we're running an analysis
    with the full dataset.
  • 45:53 - 45:58
    We have like 300 people that
    we began with at Time 1,
  • 45:58 - 46:02
    and then like at Time 8 or 9.
  • 46:02 - 46:04
    I don't remember how many
    times we collected data,
  • 46:04 - 46:08
    but many times, we
    have about 200 people.
  • 46:08 - 46:10
    We have about 100
    people that we lost,
  • 46:10 - 46:14
    and it could be that we lost
    these people because of
  • 46:14 - 46:18
    a specific reason or
    they just decided
  • 46:18 - 46:21
    not to participate
    for a random reason.
  • 46:21 - 46:23
    But some ways that
    we can look at it,
  • 46:23 - 46:24
    there's analysis
    that I have to do
  • 46:24 - 46:27
    this week when I
    finish teaching,
  • 46:27 - 46:28
    is to assess whether
  • 46:28 - 46:30
    our participants are
    missing at random.
  • 46:30 - 46:33
    There are some statistical
    techniques that you can use.
  • 46:33 - 46:37
    But let's say that in a
    study that we did use,
  • 46:37 - 46:38
    I should share this favor
  • 46:38 - 46:39
    with you because you
    probably think I'm lying,
  • 46:39 - 46:42
    but we basically
    fat shamed women.
  • 46:42 - 46:44
    I didn't was one
    of my colleagues.
  • 46:44 - 46:48
    Don't get angry at me. We had
  • 46:48 - 46:49
    overweight women, and
    we recruited them.
  • 46:49 - 46:52
    I'm overweight,
    too, so I feel it.
  • 46:52 - 46:55
    They were either in
    a condition where
  • 46:55 - 46:56
    they were fat
    shamed or they were
  • 46:56 - 46:58
    made to feel embarrassed
    about their weight.
  • 46:58 - 47:02
    They were in a dating
    scenario where very fit male,
  • 47:02 - 47:03
    they're all heterosexual, too,
  • 47:03 - 47:05
    would interact with them,
  • 47:05 - 47:07
    and it was a pretend
    date scenario
  • 47:07 - 47:09
    where they would feel a lot of
  • 47:09 - 47:10
    self-consciousness or
  • 47:10 - 47:12
    a scenario in which
    they didn't have
  • 47:12 - 47:15
    to really show their weight
    to the other person.
  • 47:15 - 47:19
    But we would have attrition
    if more people in
  • 47:19 - 47:21
    the fat shaming condition quit
  • 47:21 - 47:24
    the study relative to
    the other condition.
  • 47:24 - 47:27
    We're saying that any effects
  • 47:27 - 47:28
    on the dependent
    variable that we
  • 47:28 - 47:30
    see aren't necessarily due to
  • 47:30 - 47:33
    our manipulation of the
    independent variable,
  • 47:33 - 47:36
    but might be because
    we fat shamed women,
  • 47:36 - 47:37
    and they got upset,
  • 47:37 - 47:38
    so they dropped
    out of the study.
  • 47:38 - 47:40
    That means that it's systematic.
  • 47:40 - 47:42
    It happens in a
    specific condition.
  • 47:42 - 47:48
    Does that make sense? Alycia?
  • 47:50 - 47:55
    Attrition has to do
    with the number of
  • 47:55 - 47:57
    participants you have at
  • 47:57 - 48:00
    any given time during
    the experiment?
  • 48:00 - 48:02
    It has to do with one,
  • 48:02 - 48:05
    the reasons for why they quit.
  • 48:05 - 48:09
    Is there a reason that's
    common among them?
  • 48:09 - 48:14
    Or is it just chance
    that they dropped out?
  • 48:14 - 48:16
    If we had an equal number
    of participants in
  • 48:16 - 48:18
    the fat shaming versus the non
  • 48:18 - 48:19
    fat shaming condition drop out,
  • 48:19 - 48:20
    we could say, well, maybe people
  • 48:20 - 48:22
    are experiencing midterms.
  • 48:22 - 48:24
    They're really stressed out.
  • 48:24 - 48:26
    But if we have only people in
  • 48:26 - 48:27
    the fat shaming
    condition drop out,
  • 48:27 - 48:29
    then we're like, well,
  • 48:29 - 48:32
    it's because they're
    experiencing this threat
  • 48:32 - 48:34
    and our independent variable
  • 48:34 - 48:36
    might be too threatening
    and they're dropping out.
  • 48:36 - 48:39
    Thus this is an
    attrition threat.
  • 48:39 - 48:41
    Our independent
    variables causing
  • 48:41 - 48:43
    people to drop out of our study.
  • 48:43 - 48:48
    That's one, you lose
    people systematically.
  • 48:48 - 48:52
    Two, if people that are either
  • 48:52 - 48:54
    really extreme scores or
  • 48:54 - 48:57
    really extreme scores
    drop out of your study,
  • 48:57 - 49:00
    that affects your scores on
    your dependent variable.
  • 49:00 - 49:03
    What we're looking
    for here is just,
  • 49:03 - 49:06
    we're talking about
    internal validity,
  • 49:06 - 49:07
    we're talking about
    whether there is
  • 49:07 - 49:10
    anything like a little girl
    hiding behind the tree
  • 49:10 - 49:14
    that could explain changes
    in your dependent variable.
  • 49:14 - 49:16
    If we have all the women in
  • 49:16 - 49:19
    the fat shaming condition quit,
  • 49:19 - 49:21
    then when we run
    the analysis and we
  • 49:21 - 49:23
    found significant
    differences, yeah,
  • 49:23 - 49:25
    it might be because
    we fat shamed women,
  • 49:25 - 49:26
    but it could also be
  • 49:26 - 49:30
    because some of the women
    dropped out of the study.
  • 49:30 - 49:33
    There's an alternative
    explanation for
  • 49:33 - 49:36
    the changes in our
    dependent variable.
  • 49:37 - 49:43
    Is that more clear? It's
    okay if you say no.
  • 49:43 - 49:45
    That makes more sense.
  • 49:46 - 49:47
    Rick?
  • 49:47 - 49:49
    It makes sense.
  • 49:49 - 49:52
    How can it be prevented?
  • 49:52 - 49:55
    One way that it can
    be prevented is if
  • 49:55 - 49:58
    these people drop
    out of a study,
  • 49:58 - 50:03
    remove all of their scores
    completely from the data.
  • 50:03 - 50:06
    You remove them from
    pre-test average,
  • 50:06 - 50:07
    so it doesn't affect your scores
  • 50:07 - 50:09
    on the dependent
    variable as much.
  • 50:09 - 50:12
    The approach that we're taking
  • 50:12 - 50:16
    because we want the
    analysis that we are doing,
  • 50:16 - 50:17
    you'll probably learn about 467,
  • 50:17 - 50:21
    468 requires a minimum
    number of participants,
  • 50:21 - 50:25
    and we're barely
    meeting that number,
  • 50:25 - 50:28
    so we don't want to
    eliminate any people.
  • 50:28 - 50:31
    We're looking at pre-test
    scores of dropouts.
  • 50:31 - 50:34
    If they have extreme scores,
  • 50:34 - 50:35
    then they're more
    likely to threaten
  • 50:35 - 50:38
    the internal validity than
    they have moderate scores.
  • 50:38 - 50:40
    We're looking at
    their scores to see
  • 50:40 - 50:41
    whether they have
    very extreme scores,
  • 50:41 - 50:42
    and if they don't going
    to include them in
  • 50:42 - 50:44
    the data because we
    can argue that they're
  • 50:44 - 50:49
    not necessarily affecting
    our dependent variable.
  • 50:49 - 50:52
    Does that make sense?
  • 50:53 - 51:02
    Rick? It's a lot.
  • 51:02 - 51:04
    My mind was wondering.
  • 51:04 - 51:09
    No, it's okay. Ways
    to prevent it,
  • 51:09 - 51:11
    drop their entire beta
  • 51:11 - 51:14
    set or look at the pretest
    scores of dropout,
  • 51:14 - 51:17
    see if there's a specific
    reason why they dropped out.
  • 51:17 - 51:19
    If they aren't extreme scores,
  • 51:19 - 51:21
    you can include them in
    the dataset so that you
  • 51:21 - 51:24
    can still have more data points
  • 51:24 - 51:26
    to make stronger predictions.
  • 51:27 - 51:29
    That makes sense.
  • 51:30 - 51:33
    Haley, how are you doing?
  • 51:33 - 51:36
    I think I'm getting it.
  • 51:37 - 51:43
    It depends on if they're
    fitting within that average,
  • 51:43 - 51:44
    they're just put them back in
  • 51:44 - 51:45
    because they're not
    going to affect it.
  • 51:45 - 51:47
    They're not going to affect it.
  • 51:47 - 51:49
    It's no harm in including them.
  • 51:49 - 51:52
    But there is a harm in including
    them if you're saying,
  • 51:52 - 51:54
    Time 1 scores are
  • 51:54 - 51:57
    significantly higher
    than Time 2 scores,
  • 51:57 - 51:59
    but their mean only might be
  • 51:59 - 52:02
    higher because of
    these two people.
  • 52:02 - 52:03
    I got it.
  • 52:03 - 52:05
    But if you remove
    these two people,
  • 52:05 - 52:08
    then you can look at well,
    actually, I can't cover it.
  • 52:09 - 52:12
    Pretend these two
    scores don't exist.
  • 52:12 - 52:14
    If you look at just
    the orange dots,
  • 52:14 - 52:16
    they look almost
    exactly the same.
  • 52:16 - 52:18
    Then you would say there's
  • 52:18 - 52:19
    no significant
    difference on whatever
  • 52:19 - 52:23
    your score is between
    Type 1 and Time 2.
  • 52:24 - 52:27
    These people would be affecting
  • 52:27 - 52:30
    your interpretation
    of the results,
  • 52:30 - 52:32
    whereas if these people
    you remove them,
  • 52:32 - 52:36
    their average would still
    look the same as that one.
  • 52:36 - 52:39
    It wouldn't affect your
    interpretation of the results.
  • 52:41 - 52:45
    Is that This is tough.
  • 52:45 - 52:49
    Yeah. Okay. You can tell me
    if it doesn't make sense,
  • 52:49 - 52:51
    and then I'll try to figure out
  • 52:51 - 52:54
    different ways to
    talk about them.
  • 52:54 - 52:56
    But we'll review it on Wednesday
  • 52:56 - 52:57
    to see how well it's stuck.
  • 52:57 - 52:59
    Okay, so testing threats.
  • 52:59 - 53:01
    So what's a testing threat?
  • 53:01 - 53:03
    There's a type of order effect
  • 53:03 - 53:05
    in which there is a change in
  • 53:05 - 53:07
    participants as a
    result of experiencing
  • 53:07 - 53:11
    the dependent variable
    to test more than once.
  • 53:11 - 53:13
    Let's say that I
    was testing people
  • 53:13 - 53:16
    on let's say that I was
  • 53:16 - 53:17
    testing all of you
  • 53:17 - 53:20
    on the same questions
    over and over again.
  • 53:20 - 53:22
    I tested you on the questions I
  • 53:22 - 53:25
    gave you today and you did,
  • 53:25 - 53:27
    let's say, an eight out of t10.
  • 53:27 - 53:30
    Then I tested you
    again tomorrow,
  • 53:30 - 53:32
    and you got a 10 out of 10.
  • 53:32 - 53:34
    One argument that
    could be made is
  • 53:34 - 53:36
    that I'm a really great teacher,
  • 53:36 - 53:38
    and I taught you
    really well today.
  • 53:38 - 53:40
    That's why you
    increased in scores.
  • 53:40 - 53:43
    But the testing
    threat would argue,
  • 53:43 - 53:46
    I didn't really do
    that great of a job.
  • 53:46 - 53:48
    It's just because you've been
    exposed to the questions,
  • 53:48 - 53:50
    and that's what made you improve
  • 53:50 - 53:53
    your performance.
    Does that make sense?
  • 53:53 - 53:54
    Yeah.
  • 53:54 - 53:59
    Okay. Great. Scores might
    go up due to practice.
  • 53:59 - 54:01
    It's called a
    practice of effect.
  • 54:01 - 54:04
    Or their scores
    might go down due
  • 54:04 - 54:05
    to fatigue the fatigue effect.
  • 54:05 - 54:07
    You might be annoyed with
    me and be like, Oh, my God,
  • 54:07 - 54:08
    I've already seen
    these questions
  • 54:08 - 54:10
    and actually gets more wrong.
  • 54:10 - 54:12
    Testing threats affect
    internal validity
  • 54:12 - 54:14
    because it's not clear
    if the treatment
  • 54:14 - 54:16
    caused a change in the
    dependent variable
  • 54:16 - 54:18
    or whether practice fatigue did.
  • 54:18 - 54:20
    Here's the ability score.
  • 54:20 - 54:23
    Let's say the ability
    on the test, pre test,
  • 54:23 - 54:25
    you don't do so hot,
  • 54:25 - 54:28
    post test, you do better.
  • 54:30 - 54:32
    Again, a treatment
    group can help you
  • 54:32 - 54:34
    avoid any testing threats.
  • 54:34 - 54:39
    Let's say that in
    the treatment group,
  • 54:39 - 54:42
    this is when you were exposed
    to me an awesome teacher,
  • 54:42 - 54:45
    and this one is when
    you were just exposed
  • 54:45 - 54:48
    to some random person on
    YouTube teaching you.
  • 54:48 - 54:50
    If I wanted to
    argue, for instance,
  • 54:50 - 54:53
    for a higher raise, saying
    that I'm an awesome teacher,
  • 54:53 - 54:54
    and I increased
    your performance,
  • 54:54 - 54:56
    I would need to show that there
  • 54:56 - 54:57
    was a significant difference
  • 54:57 - 55:00
    between the comparison group
    and the treatment group.
  • 55:00 - 55:03
    It looks here like at post test,
  • 55:03 - 55:06
    I did do a better job than
  • 55:06 - 55:08
    a random person
    that you could have
  • 55:08 - 55:11
    seen on YouTube in terms
    of improving your ability.
  • 55:11 - 55:12
    Well, that's good.
  • 55:12 - 55:15
    [LAUGHTER] This is
    just an example.
  • 55:15 - 55:17
    I'm just trying to give you guys
  • 55:17 - 55:18
    examples that might
    be relatable.
  • 55:18 - 55:20
    Cool. All right.
  • 55:20 - 55:24
    More questions or
    does this make sense?
  • 55:24 - 55:26
    It's just like being exposed to
  • 55:26 - 55:27
    the test can improve
    your performance,
  • 55:27 - 55:28
    or it can worsen
    your performance.
  • 55:28 - 55:31
    What's an example where it
    can worsen your performance?
  • 55:33 - 55:36
    Were being exposed to the?
  • 55:36 - 55:40
    Yeah, burnout but, like,
    give me an example.
  • 55:41 - 55:45
    Well, I go through
    both of those things
  • 55:45 - 55:47
    on our test when we get
  • 55:47 - 55:49
    a chance to take them
    too, the quit twice.
  • 55:49 - 55:54
    The quiz is a perfect
    example is like,
  • 55:54 - 55:57
    my God, if I got a 90,
  • 55:57 - 56:00
    do I want to go through
    that again, you know?
  • 56:00 - 56:02
    Because it's a real burnout.
  • 56:02 - 56:05
    I focus so much and
    to do it again.
  • 56:05 - 56:07
    If it's a longer test,
  • 56:07 - 56:10
    that might affect my
    score or my burnout.
  • 56:10 - 56:15
    Let's say you start off
    with 100 units of energy.
  • 56:15 - 56:18
    When you take the test,
    you get frustrated.
  • 56:18 - 56:21
    Then take the test again
    you get an eight out of 10.
  • 56:21 - 56:23
    Now, you only have
    70 units of energy,
  • 56:23 - 56:24
    so you have to take it again.
  • 56:24 - 56:27
    You might either do worse
    because you're fatigued,
  • 56:27 - 56:29
    you're missing 30
    units of energy,
  • 56:29 - 56:31
    or you might do
    better because you're
  • 56:31 - 56:32
    exposed to the same questions.
  • 56:32 - 56:36
    That's a great example
    of a testing threat.
  • 56:37 - 56:39
    What about
    instrumentation threat?
  • 56:39 - 56:42
    This one, I think is the
    easiest of all of them.
  • 56:42 - 56:46
    This is when the observers
    change the criteria over time.
  • 56:46 - 56:49
    Let's say that I
    have a test at time
  • 56:49 - 56:52
    1 and a test at time
    2, and at time 1,
  • 56:52 - 56:54
    I give you really,
    really hard questions
  • 56:54 - 56:58
    and you all do not
    hot, not great.
  • 56:58 - 57:00
    But then at time 2, I give you
  • 57:00 - 57:03
    really easy questions
    and you do better.
  • 57:03 - 57:06
    That's an instrumentation
    threat because I'm giving you
  • 57:06 - 57:08
    different ways of measuring
    your performance.
  • 57:08 - 57:11
    At time 1, I'm giving you
    really hard questions,
  • 57:11 - 57:14
    and at time 2, I'm giving
    you really easy questions.
  • 57:14 - 57:16
    It isn't that I
    taught you better,
  • 57:16 - 57:21
    it's that I gave you different
    ways of measuring ability.
  • 57:21 - 57:23
    The researcher uses
    different forms of
  • 57:23 - 57:27
    a pretest and post test
    that aren't equivalent.
  • 57:27 - 57:29
    One way to prevent this is to
  • 57:29 - 57:31
    use a post-test only design.
  • 57:31 - 57:33
    Randomly assign people
    to either have me as
  • 57:33 - 57:36
    an instructor or random YouTube
    person as an instructor,
  • 57:36 - 57:38
    and then measure
    their performance on
  • 57:38 - 57:44
    moderate pace or moderately
    difficult questions.
  • 57:44 - 57:47
    But if you do need a
    pretest post-test design,
  • 57:47 - 57:49
    you should make sure
    that the pretest
  • 57:49 - 57:50
    and the post-test
    forms are equivalent.
  • 57:50 - 57:52
    I really wanted to see
  • 57:52 - 57:54
    whether my performance as
  • 57:54 - 57:56
    an instructor affected
    your learning,
  • 57:56 - 57:59
    I would have so this is what
    you guys are taking, right?
  • 57:59 - 58:00
    You guys are taking a pretest
  • 58:00 - 58:02
    to see what you know
    about research methods.
  • 58:02 - 58:04
    That's one of the extra
    credit assignments
  • 58:04 - 58:04
    and then you're taking
  • 58:04 - 58:06
    a post-test to see how
  • 58:06 - 58:08
    well I did in
    teaching and how well
  • 58:08 - 58:11
    you retained the material.
  • 58:15 - 58:18
    How can they be prevented?
  • 58:18 - 58:22
    Let's see. How can
    they be prevented?
  • 58:22 - 58:25
    A post-test only design or make
  • 58:25 - 58:28
    sure that pre test and
    post tests are equivalent.
  • 58:30 - 58:32
    Post test would be
    between subjects,
  • 58:32 - 58:36
    so I would randomly assign
    you to either me or YouTube
  • 58:36 - 58:40
    and give you same level
    of difficulty questions,
  • 58:40 - 58:42
    or I would have a pre
    test and a post test.
  • 58:42 - 58:44
    Kind of what you're doing in
    this class. Take a pre test.
  • 58:44 - 58:46
    How much do you know
    about research methods?
  • 58:46 - 58:48
    Take the class and then see
  • 58:48 - 58:51
    how much you learn about
    research methods in the class.
  • 58:51 - 58:54
    What's the difference between
  • 58:54 - 58:57
    instrumentation versus
    testing threads?
  • 58:57 - 58:59
    Because they both have to do
  • 58:59 - 59:03
    with maybe seeing
    something repeatedly.
  • 59:03 - 59:08
    But instrumentation is the
    measurement instrument
  • 59:08 - 59:10
    has changed from
    time 1 to time 2.
  • 59:10 - 59:12
    I use either really
    difficult or really
  • 59:12 - 59:14
    easy questions
    depending on the time,
  • 59:14 - 59:16
    and testing effects happen when
  • 59:16 - 59:20
    the participant changes
    from time 1 to time 2.
  • 59:20 - 59:23
    Testing is that you actually
  • 59:23 - 59:27
    got better at knowing
    the material.
  • 59:27 - 59:29
    You got practice with
  • 59:29 - 59:33
    the material or you got
    fatigued from the material.
  • 59:33 - 59:34
    This would be testing.
  • 59:34 - 59:36
    It's something that
    changes within you.
  • 59:36 - 59:39
    Instrumentation,
    it's something that
  • 59:39 - 59:41
    happens on the measure.
  • 59:41 - 59:44
    It's either really hard
    measure or really easy measure
  • 59:44 - 59:47
    or we have one measure
    of depression,
  • 59:47 - 59:49
    then we change it to another
    measure of depression.
  • 59:49 - 59:51
    That's the difference between
  • 59:51 - 59:53
    instrumentation and testing.
  • 59:53 - 59:55
    Instrumentation is more
    about the instrument.
  • 59:55 - 60:04
    Testing is about the participant.
    Alisa you are thrilled.
  • 60:04 - 60:08
    Instrumentation is
    like you're changing
  • 60:08 - 60:12
    the methods you use
    throughout the experiment.
  • 60:12 - 60:13
    The methods might be the
  • 60:13 - 60:17
    same except that the
    measure is different.
  • 60:17 - 60:18
    Let's say that you were looking
  • 60:18 - 60:20
    at whether you can
    make introverts more
  • 60:20 - 60:22
    extroverted by making them
  • 60:22 - 60:26
    attend a party with
    mostly extroverts.
  • 60:26 - 60:29
    You measured introvert.
    You're like,
  • 60:29 - 60:30
    It's not going to work.
  • 60:30 - 60:32
    But let's say
    measure introversion
  • 60:32 - 60:34
    with one personality scale,
  • 60:34 - 60:35
    and then after the party,
  • 60:35 - 60:38
    you measured introversion with
    another personality scale.
  • 60:38 - 60:41
    That would be an
    instrumentation threat.
  • 60:42 - 60:50
    A testing threat might be
    something like if you measured
  • 60:50 - 60:54
    the extent to which
    introverts are
  • 60:54 - 60:58
    happy after attending a party,
  • 60:58 - 60:59
    you're like, Yeah, introverts
  • 60:59 - 61:01
    just an argument might be made.
  • 61:01 - 61:03
    Introverts just need to
    hang out with more people,
  • 61:03 - 61:05
    and they'll become extroverted.
  • 61:05 - 61:09
    You take their levels
    of happiness at time 1,
  • 61:09 - 61:11
    and then you take their
    happiness at time 2,
  • 61:11 - 61:13
    which is after the party,
  • 61:13 - 61:15
    and they might be more upset,
  • 61:15 - 61:16
    not necessarily
    because of the party,
  • 61:16 - 61:17
    but maybe because of the amount
  • 61:17 - 61:19
    of time that they
    had to spend with
  • 61:19 - 61:22
    other people or other factors.
  • 61:22 - 61:24
    Yeah. Does that make sense?
  • 61:24 - 61:26
    The participant or the
    instrument changes.
  • 61:26 - 61:28
    These are examples
    I'm just coming
  • 61:28 - 61:29
    up from the top of my head,
  • 61:29 - 61:31
    so if they're awful, I'm sorry.
  • 61:31 - 61:33
    But I can come up
    with different ones,
  • 61:33 - 61:35
    too. Combined threats.
  • 61:35 - 61:40
    Sometimes the threats combine
    to create a super threat.
  • 61:40 - 61:43
    There's a selection
    history threat.
  • 61:43 - 61:45
    This is when an outside event
  • 61:45 - 61:47
    or factor systematically affects
  • 61:47 - 61:52
    participants at one level of
    the independent variable.
  • 61:52 - 61:53
    Let's say that students at
  • 61:53 - 61:56
    one university were in
    your treatment group,
  • 61:56 - 61:58
    so students at PSU were
    in my treatment group,
  • 61:58 - 62:01
    and students at WU were
    in my control group,
  • 62:01 - 62:05
    and I wanted to see the effects
    of meditation on stress.
  • 62:05 - 62:07
    Let's say that during
    the course of the study,
  • 62:07 - 62:11
    a stressful event occurs at PSU,
  • 62:11 - 62:14
    that would affect the
    results of your study.
  • 62:14 - 62:16
    That's a history threat,
  • 62:16 - 62:18
    and it's also a selection
    threat because it
  • 62:18 - 62:21
    only occurs at one
    of the two places.
  • 62:22 - 62:26
    What about a selection
    attrition threat?
  • 62:26 - 62:27
    This is when participants in one
  • 62:27 - 62:29
    experimental group
    experience attrition.
  • 62:29 - 62:31
    That's what I was
    talking about with
  • 62:31 - 62:33
    women that are fat chained,
  • 62:33 - 62:34
    we call it weight stigma.
  • 62:34 - 62:36
    If we have more participants
  • 62:36 - 62:38
    in one experimental group
    experience attrition.
  • 62:38 - 62:42
    If more people in the weight
    stigma condition drop out,
  • 62:42 - 62:45
    then that is a selection
    attrition threat.
  • 62:45 - 62:48
    Let's say the participants
    in one study or
  • 62:48 - 62:50
    one group have to travel
    one mile for the study,
  • 62:50 - 62:52
    and participants in the
    other group have to
  • 62:52 - 62:54
    travel 20 miles for the study.
  • 62:54 - 62:58
    You might have more people
    drop out in which condition.
  • 63:04 - 63:07
    The 20 mile group?
  • 63:07 - 63:09
    Oh, yeah.
  • 63:09 - 63:11
    Zone it out. Yeah.
  • 63:11 - 63:13
    The people that got
    to drive further.
  • 63:13 - 63:15
    They have to walk. You have to
  • 63:15 - 63:17
    walk either 1 mile or 20 miles.
  • 63:17 - 63:18
    Oh, what? Oh.
  • 63:18 - 63:21
    Yeah. I might walk.
  • 63:21 - 63:24
    You might have more attrition in
  • 63:24 - 63:26
    the 20 mile group due to
    the distance from the lab.
  • 63:26 - 63:27
    You can't be sure if
  • 63:27 - 63:29
    the differences between
    the groups were
  • 63:29 - 63:31
    due to the independent variable
  • 63:31 - 63:33
    or the distance in attrition.
  • 63:33 - 63:35
    All these threats to
    internal validity
  • 63:35 - 63:36
    are essentially saying,
  • 63:36 - 63:38
    there are all these
    other things that
  • 63:38 - 63:40
    could be causing your
    dependent variable,
  • 63:40 - 63:42
    and you need to
    be aware of them.
  • 63:43 - 63:45
    We're doing a lot of
  • 63:45 - 63:48
    the things that we should be
    doing in your experiments or
  • 63:48 - 63:49
    when I talk to you about
  • 63:49 - 63:51
    your experiments to make
    sure that there are
  • 63:51 - 63:52
    no other variables that
  • 63:52 - 63:55
    could explain changes in
    your dependent variable.
  • 63:55 - 63:56
    Like for Rick, we talked about
  • 63:56 - 63:59
    Pepsi versus Coke drinkers,
  • 63:59 - 64:01
    Alesia we could talk
  • 64:01 - 64:06
    about the extent of whether
    people live alone or not
  • 64:06 - 64:08
    during the quarantine
    because that could
  • 64:08 - 64:14
    affect their levels of
    introversion versus extroversion.
  • 64:14 - 64:16
    Maybe people can change.
  • 64:16 - 64:19
    I feel like we're all
    becoming a lot more awkward.
  • 64:19 - 64:20
    I don't know if that's
    correct or not,
  • 64:20 - 64:23
    but so I'm fully vaccinated.
  • 64:23 - 64:24
    One of my friends
    is too, and we had
  • 64:24 - 64:26
    a distance lunch recently.
  • 64:26 - 64:28
    I was just really awkward.
  • 64:28 - 64:29
    I mean, all of it
    is really awkward.
  • 64:29 - 64:31
    Like, you have to sit far apart,
  • 64:31 - 64:36
    and then anyway, so
    selection attrition threat.
  • 64:36 - 64:38
    Yes. Does that make sense?
  • 64:38 - 64:42
    We're redefining our
    cultural interactions.
  • 64:42 - 64:44
    There you go. Yeah, we are.
  • 64:44 - 64:45
    It's really weird and, like,
  • 64:45 - 64:46
    when we started zooming,
  • 64:46 - 64:49
    I hate I've never had
    to look on my face
  • 64:49 - 64:52
    before this often [LAUGHTER]
  • 64:52 - 64:54
    I know. I'm hard.
  • 64:54 - 64:57
    Yeah. Especially when
    you're teaching.
  • 64:58 - 65:01
    Any other comments or questions?
  • 65:01 - 65:03
    See, that's another
    interesting Razors question.
  • 65:03 - 65:05
    Like, how are we changing
  • 65:05 - 65:11
    our cultural expectations
    about social interactions?
  • 65:11 - 65:15
    Right now, right in this moment.
  • 65:15 - 65:18
    It is very, very
    awkward and weird.
  • 65:18 - 65:22
    Some people, okay,
    so short side note.
  • 65:22 - 65:24
    Some people are worried
    about children not being
  • 65:24 - 65:26
    able to detect
    emotional expressions.
  • 65:26 - 65:28
    Especially among
    infants and toddlers,
  • 65:28 - 65:30
    because that's when they
  • 65:30 - 65:32
    learn what happy face
  • 65:32 - 65:33
    and angry face and all
    this stuff looks like.
  • 65:33 - 65:35
    If they're going out
    and they're I can't
  • 65:35 - 65:37
    imagine being an infant
    or toddler right now.
  • 65:37 - 65:38
    Oh, no.
  • 65:38 - 65:41
    Your norm is just
    seeing, people's eyes.
  • 65:41 - 65:44
    No, but they actually
    had some research,
  • 65:44 - 65:46
    and they showed that
    their detection
  • 65:46 - 65:48
    of emotional expression
    isn't changing.
  • 65:48 - 65:50
    But it must be really
    weird for, like,
  • 65:50 - 65:52
    little babies and toddlers,
  • 65:52 - 65:53
    like in the next few
    years and they're like,
  • 65:53 - 65:58
    why isn't anyone wearing a
    mask anymore? If that happens.
  • 65:58 - 66:02
    I kind of have that experience
    at work, 'cause, like,
  • 66:02 - 66:06
    I think most of my expression
    comes from my mouth,
  • 66:06 - 66:07
    like, whether I'm
    frowning or whether,
  • 66:07 - 66:08
    like, there's a small smile,
  • 66:08 - 66:10
    but, like, we have the mask,
  • 66:10 - 66:12
    so I feel like people when
    they're talking to me,
  • 66:12 - 66:13
    they can't tell, like,
  • 66:13 - 66:14
    I might be smiling, but
  • 66:14 - 66:15
    they're probably
    looking at me thinking,
  • 66:15 - 66:16
    She's so pissed off
  • 66:16 - 66:18
    right now [LAUGHTER]
    even though I'm not.
  • 66:18 - 66:20
    I do a more squinty smile now.
  • 66:20 - 66:22
    Like, that's my smile when I'm
  • 66:22 - 66:24
    wearing my mask just to
    remind people that I'm,
  • 66:24 - 66:27
    it's very, very strange.
  • 66:28 - 66:30
    I have two more
    slides to go before I
  • 66:30 - 66:33
    switch to something else.
  • 66:34 - 66:36
    This one should be
    easy relative to
  • 66:36 - 66:38
    the other internal threats.
  • 66:38 - 66:42
    Three potential internal
    validity threats in any study.
  • 66:42 - 66:46
    Now that we've talked about
    the other six, observer bias.
  • 66:46 - 66:49
    This is when the
    researchers expectations
  • 66:49 - 66:52
    influence how we
    interpret the results.
  • 66:52 - 66:56
    An example might be for
    the depression study.
  • 66:56 - 66:58
    Doctor Yuki might be
    a biased observer
  • 66:58 - 66:59
    of patients depression.
  • 66:59 - 67:02
    She expects to see our
    patients improve whether they
  • 67:02 - 67:04
    do or do not. She
    might rate them.
  • 67:04 - 67:05
    Instead of having them fill out
  • 67:05 - 67:06
    a self support on depression,
  • 67:06 - 67:09
    she might rate how
    depressed they seem.
  • 67:09 - 67:12
    She might manipulate the data
  • 67:12 - 67:14
    to make it look like they
    seem less depressed.
  • 67:14 - 67:18
    Nickle may also be a biased
    observer of his campers.
  • 67:18 - 67:20
    He might expect the low
    sugar diet to work,
  • 67:20 - 67:23
    so he views the boys post test
    behavior more positively.
  • 67:23 - 67:25
    This is one of the
    reasons why we
  • 67:25 - 67:30
    have confederates or other
    people rate our data.
  • 67:30 - 67:31
    For instance, I have
  • 67:31 - 67:33
    research assistants who
    I might say, like, oh,
  • 67:33 - 67:35
    can you rate this
    data for positivity,
  • 67:35 - 67:38
    negativity, all these
    other adjectives.
  • 67:38 - 67:40
    But I'm really looking for
  • 67:40 - 67:43
    is how biased people's
    responses are.
  • 67:43 - 67:46
    But by including
    different measures
  • 67:46 - 67:49
    and by not letting them
    know what my hypothesis is,
  • 67:49 - 67:51
    I'm removing observer bias
  • 67:51 - 67:53
    because I might if I were
    to look at the data,
  • 67:53 - 67:56
    I'm like, oh, this
    guy's clearly biased.
  • 67:56 - 67:59
    I might inadvertently
    make my data look
  • 67:59 - 68:01
    and analyze it in
  • 68:01 - 68:04
    such a way that it would be
    statistically significant.
  • 68:04 - 68:07
    That's why there are lots
    of checks to make sure that
  • 68:07 - 68:10
    your data are interpreted
  • 68:10 - 68:12
    in the most objective
    way possible
  • 68:12 - 68:14
    to reduce observer bias.
  • 68:15 - 68:17
    Although comparison
    groups can prevent
  • 68:17 - 68:19
    many threats to
    internal validity,
  • 68:19 - 68:22
    they don't necessarily
    control for observer bias.
  • 68:22 - 68:25
    Even if doctor Yuki used a
    no therapy comparison group,
  • 68:25 - 68:27
    observaive bias
    could still occur.
  • 68:27 - 68:29
    If she knew the participants
    were in which group,
  • 68:29 - 68:31
    her biases could lead her
    to see more improvement
  • 68:31 - 68:33
    in the therapy group than
    in the comparison group.
  • 68:33 - 68:36
    We have to be aware
    of our own bias.
  • 68:36 - 68:40
    A way to circumvent
    that also is by using
  • 68:40 - 68:43
    self report measures because
  • 68:43 - 68:46
    participants have to
    answer those questions,
  • 68:46 - 68:48
    and it's not us
    affecting the data.
  • 68:48 - 68:51
    However, when participants
    are affected,
  • 68:51 - 68:55
    this is called demand
    characteristics.
  • 68:55 - 68:57
    Demand characteristics
    is a bias that
  • 68:57 - 68:59
    occurs when participants
    figure out what
  • 68:59 - 69:01
    a research study is
    about and change
  • 69:01 - 69:04
    their behavior in the
    expected direction.
  • 69:04 - 69:05
    Observer bias is about
  • 69:05 - 69:09
    the researcher changing how
    they interpret the results.
  • 69:09 - 69:11
    Demand characteristics is about
  • 69:11 - 69:14
    the participant figuring out
    what the study is about.
  • 69:14 - 69:16
    Sometimes participants want
    to be good participants.
  • 69:16 - 69:17
    I think most of
    the time they do.
  • 69:17 - 69:20
    They might answer your surveys
    in a way that supports
  • 69:20 - 69:23
    your hypotheses or what they
    think your hypotheses are.
  • 69:23 - 69:27
    Sometimes we have what is it?
  • 69:27 - 69:29
    Antagonistic
    participants, so they
  • 69:29 - 69:30
    figure out your hypothesis,
  • 69:30 - 69:31
    and then they're like,
  • 69:31 - 69:32
    I'm not going to prove
    your hypothesis,
  • 69:32 - 69:34
    right, or I'm not going to
    support your hypothesis.
  • 69:34 - 69:37
    They answer questions in
    a complete opposite way.
  • 69:38 - 69:41
    One way that we can control
    for observer bias and
  • 69:41 - 69:43
    demand characteristics is by
  • 69:43 - 69:46
    using a double blind mask study.
  • 69:46 - 69:49
    What this means is,
  • 69:49 - 69:51
    I, as the experimenter,
  • 69:51 - 69:57
    would create a sheet
    that had numbers on it.
  • 69:57 - 70:00
    I would be the one
    who knows that one
  • 70:00 - 70:06
    equals pre COVID and two
    equals during COVID.
  • 70:06 - 70:08
    I would be the one who knows
  • 70:08 - 70:10
    what the experimental
    conditions are.
  • 70:10 - 70:12
    But let's say Alesia and
  • 70:12 - 70:14
    Rick and Hey are my
    research assistants,
  • 70:14 - 70:16
    and all you know is,
    if there are one,
  • 70:16 - 70:17
    you put them on this
    computer, if there are two,
  • 70:17 - 70:19
    you put them on that computer.
  • 70:19 - 70:21
    You as experimenter don't know
  • 70:21 - 70:23
    what condition the
    participants are in,
  • 70:23 - 70:25
    and the participants themselves
  • 70:25 - 70:27
    don't know what
    experiment they're in
  • 70:27 - 70:29
    either because they only get
  • 70:29 - 70:32
    exposed to one of
    the two surveys.
  • 70:32 - 70:34
    Does that make sense? If you as
  • 70:34 - 70:36
    a research assistants are
  • 70:36 - 70:37
    they're in the room
    with a participant,
  • 70:37 - 70:38
    you don't know what
    condition they're in.
  • 70:38 - 70:40
    You can't affect their behavior.
  • 70:40 - 70:41
    You can't interpret
    their behavior in
  • 70:41 - 70:43
    a way that's consistent with
  • 70:43 - 70:45
    your manipulation of the
    independent variable
  • 70:45 - 70:48
    because you don't know
    what condition they're in,
  • 70:48 - 70:50
    and the participants can't
  • 70:50 - 70:52
    behave in a way that's
    consistent with
  • 70:52 - 70:54
    your hypotheses because
    they don't know
  • 70:54 - 70:58
    what condition they're in or
    how many conditions exist.
  • 70:58 - 71:03
    Does that make sense? If you
    were in one of my studies,
  • 71:03 - 71:04
    you might be in one of
  • 71:04 - 71:06
    four conditions or one
    of five conditions.
  • 71:06 - 71:09
    Even if you tried to guess
    what my study was about,
  • 71:09 - 71:11
    you might not be correct.
  • 71:11 - 71:14
    That's one way to avoid
    demand characteristics.
  • 71:19 - 71:22
    If a double-blind
    study isn't feasible,
  • 71:22 - 71:24
    sometimes it's really
    difficult, especially,
  • 71:24 - 71:28
    let's say that Computer 1
    breaks down and you're like,
  • 71:28 - 71:29
    oh, my God, Computer
    1 broke down,
  • 71:29 - 71:30
    so I can't assign
    participants to that.
  • 71:30 - 71:32
    Then I would have to tell you,
  • 71:32 - 71:35
    click on the "Pre-COVID"
    survey for this person,
  • 71:35 - 71:37
    then click on the
    "Post-COVID" survey.
  • 71:37 - 71:40
    That would be a mask study.
  • 71:41 - 71:44
    The participants might know
    which group they're in,
  • 71:44 - 71:47
    but other people might not.
  • 71:47 - 71:50
    They might know based on
  • 71:50 - 71:52
    the survey tab that they're
    in the pre-COVID group.
  • 71:52 - 71:55
    You might know that they're
    in the pre-COVID group,
  • 71:55 - 71:56
    but someone else who might be
  • 71:56 - 71:57
    observing the study
    and looking at
  • 71:57 - 72:01
    the behavior might not know
    what group they're in.
  • 72:01 - 72:05
    We would try to mitigate
  • 72:05 - 72:07
    observer bias by doing
  • 72:07 - 72:10
    that and also demand
    characteristics.
  • 72:10 - 72:11
    But the best, of course,
  • 72:11 - 72:13
    is the double-blind, but
  • 72:13 - 72:14
    it can get pretty
    complicated really quick.
  • 72:14 - 72:16
    Another way that it can
    get really messed up is,
  • 72:16 - 72:20
    let's say, Condition
    1 is pre-COVID,
  • 72:20 - 72:23
    and Condition 2 is during COVID.
  • 72:23 - 72:25
    I wrote that down somewhere,
  • 72:25 - 72:27
    and then I threw away the paper,
  • 72:27 - 72:28
    and then all I have is
  • 72:28 - 72:30
    there's people in Condition
    1 and Condition 2,
  • 72:30 - 72:32
    and I'm like, I don't
    know what they mean.
  • 72:32 - 72:36
    That's another way that
    double-blind studies can fail.
  • 72:37 - 72:42
    The placebo effects. You
    guys like placebo effects.
  • 72:42 - 72:45
    Everybody likes them, because
  • 72:45 - 72:47
    this effect is
    present when people
  • 72:47 - 72:48
    receive a treatment and improve,
  • 72:48 - 72:50
    but only because they
    believe that they are
  • 72:50 - 72:54
    receiving a valid or
    effective treatment.
  • 72:54 - 72:57
    There are ways
    that we can design
  • 72:57 - 72:59
    a study to rule out
    the placebo effect.
  • 72:59 - 73:03
    This is a double-blind
    placebo study.
  • 73:03 - 73:06
    Let's say that we
    had this experiment.
  • 73:06 - 73:07
    Participants are
    told that they're
  • 73:07 - 73:08
    receiving a new therapy,
  • 73:08 - 73:11
    pill, or injection, but in fact,
  • 73:11 - 73:13
    it's missing the
    active ingredient,
  • 73:13 - 73:14
    or they may be told that
  • 73:14 - 73:16
    they're getting a
    new type of therapy,
  • 73:16 - 73:17
    but in fact, they simply
  • 73:17 - 73:20
    chatted with someone and
    didn't get any therapy.
  • 73:20 - 73:22
    Nonetheless,
    participants may improve
  • 73:22 - 73:23
    because they thought that
    they had the therapy.
  • 73:23 - 73:25
    It's important to note that
  • 73:25 - 73:26
    placebo effects
    aren't imaginary,
  • 73:26 - 73:29
    but placebos can be
    strong treatments.
  • 73:29 - 73:34
    How can we design studies to
    rule out the placebo effect?
  • 73:35 - 73:38
    Have any of you experienced
    a placebo effect?
  • 73:38 - 73:41
    Probably.
  • 73:41 - 73:43
    Can you think of it? It usually
  • 73:43 - 73:47
    happens below
    conscious awareness.
  • 73:48 - 73:51
    Can you think of a time?
  • 73:51 - 73:52
    Have you taken emergency,
  • 73:52 - 73:56
    and that made your cold last
    a shorter amount of time?
  • 73:57 - 73:59
    Or you avoided getting
  • 73:59 - 74:00
    a cold because you
    took an emergency?
  • 74:00 - 74:02
    There are a lot of
    things like that
  • 74:02 - 74:04
    that aren't empirically studied,
  • 74:04 - 74:07
    necessarily, but that we all do.
  • 74:07 - 74:11
    Even as scientists, that we
    might do things like that.
  • 74:11 - 74:15
    No placebo effect?
  • 74:16 - 74:18
    In the figure on the left,
  • 74:18 - 74:20
    so this figure right here,
  • 74:20 - 74:24
    you can see that both
    groups symptoms.
  • 74:24 - 74:25
    We have symptoms on the y-axis,
  • 74:25 - 74:27
    pre-test and
    post-test ratings of,
  • 74:27 - 74:32
    let's say, pain across time.
  • 74:32 - 74:35
    This is pre/post symptoms pain.
  • 74:35 - 74:39
    You can see that both groups
    decrease across time.
  • 74:39 - 74:42
    But the group in the
    true therapy condition,
  • 74:42 - 74:44
    the teal color,
  • 74:44 - 74:47
    decreased more in their
    post-test rating relative
  • 74:47 - 74:50
    to those in the placebo therapy.
  • 74:50 - 74:52
    It suggests that the
    therapy had some effect.
  • 74:52 - 74:54
    There was a placebo effect,
  • 74:54 - 74:56
    but there was also a
  • 74:56 - 74:57
    greater-than-placebo effect in
  • 74:57 - 75:00
    the true therapy condition.
  • 75:02 - 75:04
    But there could also be
  • 75:04 - 75:06
    other internal validity threats
  • 75:06 - 75:08
    that could have
    explained that result.
  • 75:08 - 75:11
    Again, that could have
    been due to maturation,
  • 75:11 - 75:13
    could have been done to
    history or aggression,
  • 75:13 - 75:15
    testing, or
    instrumentation threats.
  • 75:15 - 75:18
    Maturation, something
    happened across time.
  • 75:18 - 75:20
    Maybe their pain just
    decreased because
  • 75:20 - 75:25
    their body is healing, history.
  • 75:25 - 75:29
    What could be something
    that's a threat
  • 75:29 - 75:32
    to history with decreased pain?
  • 75:33 - 75:35
    Maybe a bomb went off
  • 75:35 - 75:38
    and other parts of
    their body hurt,
  • 75:38 - 75:42
    like their arm had
    to be amputated.
  • 75:42 - 75:43
    Their knee pain seems
  • 75:43 - 75:46
    a lot less severe relative
  • 75:46 - 75:48
    to the arm pain that
    they're experiencing.
  • 75:48 - 75:49
    That might be a history threat.
  • 75:49 - 75:51
    Rick, you seem surprised.
  • 75:51 - 75:52
    I'm just trying to
    think of something,
  • 75:52 - 75:54
    a historical event that
    could happen that could make
  • 75:54 - 75:56
    your knee pain seem less severe.
  • 75:56 - 76:00
    If something bigger
    than you happens.
  • 76:03 - 76:06
    What about regression?
  • 76:08 - 76:10
    This might happen
    when you go to the
  • 76:10 - 76:11
    doctor and they ask you,
  • 76:11 - 76:13
    on a scale 1-10, how
    much pain are you in?
  • 76:13 - 76:15
    There's a long line,
  • 76:15 - 76:18
    and you might say, I'm at
    a nine when you get there.
  • 76:18 - 76:20
    But then when they
    see you in the room,
  • 76:20 - 76:21
    you're like, not really.
  • 76:21 - 76:22
    It might be a seven.
  • 76:22 - 76:27
    That could be a regression
    test, a regression threat.
  • 76:27 - 76:32
    Testing could be what?
  • 76:32 - 76:35
    A threat to testing or
  • 76:35 - 76:40
    a testing threat is when
    the participant changes.
  • 76:51 - 76:56
    They see a nurse and
    they mention something,
  • 76:56 - 76:57
    and the nurse is like,
    oh, that's really bad,
  • 76:57 - 76:59
    or oh, that's fine.
  • 76:59 - 77:01
    Then when they see
    the actual doctor,
  • 77:01 - 77:02
    based on what the nurse said,
  • 77:02 - 77:03
    they could be like,
  • 77:03 - 77:05
    but it's not that bad oh,
  • 77:05 - 77:07
    but it's actually really bad.
  • 77:07 - 77:11
    Some outside influence can
    change your own perception.
  • 77:11 - 77:15
    That's a good example of
    testing and instrumentation.
  • 77:15 - 77:18
    Let's say that I
    measure the amount of
  • 77:18 - 77:19
    pain in your injured leg by
  • 77:19 - 77:21
    squeezing it at the
    first amount of time.
  • 77:21 - 77:23
    At the second amount of time,
  • 77:23 - 77:25
    I just give you a survey.
  • 77:25 - 77:26
    Of course, you're going to have
  • 77:26 - 77:27
    a lot more pain when I squeeze
  • 77:27 - 77:30
    your injured leg versus when
    I just ask you about it.
  • 77:30 - 77:33
    That would be an instrument
    of threat because I use
  • 77:33 - 77:37
    different measures
    of pain or symptoms.
  • 77:38 - 77:42
    I just wanted to go through
    all of them, maturation,
  • 77:42 - 77:44
    history, regression,
    testing, and
  • 77:44 - 77:47
    instrumentation. Did all
    of those make sense?
  • 77:47 - 77:50
    History would be
    the bomb going off.
  • 77:50 - 77:52
    Regression would be like,
  • 77:52 - 77:53
    before you see the
    doctor, you want to get
  • 77:53 - 77:55
    in, and you exaggerate.
  • 77:55 - 77:56
    But then, when you
    actually see the doctor,
  • 77:56 - 77:58
    you know that they're
    going to be able to tell
  • 77:58 - 78:00
    how much your pain
    is, so you reduce it.
  • 78:00 - 78:04
    Testing is you have a
    certain threshold for pain,
  • 78:04 - 78:05
    so you're like, oh, my God,
  • 78:05 - 78:07
    I'm experiencing a
    Level 8 of pain,
  • 78:07 - 78:09
    and then the nurse sees
    you and she's like,
  • 78:09 - 78:11
    no, that's not really a Level 8.
  • 78:11 - 78:13
    Level 8 is like you're
    giving birth or something.
  • 78:13 - 78:16
    You're like, so that
    changes your anchor.
  • 78:16 - 78:18
    Then instrumentation is using
  • 78:18 - 78:20
    grabbing your injured leg versus
  • 78:20 - 78:25
    giving you a survey.
    Bring it all together.
  • 78:25 - 78:28
    In order to determine
    whether there is,
  • 78:28 - 78:29
    in fact, a placebo effect,
  • 78:29 - 78:30
    the researcher might add a third
  • 78:30 - 78:31
    comparison group that doesn't
  • 78:31 - 78:34
    receive any therapy at all.
  • 78:34 - 78:36
    They don't receive
    the true therapy
  • 78:36 - 78:38
    or the placebo therapy.
  • 78:38 - 78:40
    They don't receive
    any therapy at all.
  • 78:40 - 78:44
    If you have a placebo
    effect, be here.
  • 78:45 - 78:48
    If you have a placebo effect,
  • 78:49 - 78:51
    then no treatment group should
  • 78:51 - 78:53
    improve much as a placebo group.
  • 78:53 - 78:55
    Here, we have the
    no therapy group,
  • 78:55 - 78:57
    we have the placebo
    therapy group,
  • 78:57 - 79:00
    but we do have a
    placebo effect because
  • 79:00 - 79:04
    both the placebo group and
  • 79:04 - 79:05
    the true therapy groups seem to
  • 79:05 - 79:07
    decrease in symptoms
    across time,
  • 79:07 - 79:09
    and that seems to be greater
  • 79:09 - 79:12
    for them relative to
    the no therapy group.
  • 79:12 - 79:14
    The placebo does seem to
    have a greater effect on
  • 79:14 - 79:19
    symptoms. Does that make sense?
  • 79:20 - 79:22
    The true therapy might be going
  • 79:22 - 79:26
    to the physical therapist.
  • 79:26 - 79:30
    Placebo therapy might be
    going to me and unlicensed.
  • 79:30 - 79:33
    Not at all expert on
    physical therapy,
  • 79:33 - 79:35
    but I might just, like,
  • 79:35 - 79:36
    squish your leg around.
  • 79:36 - 79:38
    That's a placebo therapy.
  • 79:38 - 79:41
    Then no therapy is
    you just go home.
  • 79:41 - 79:43
    Me just squishing your leg
    around might help you feel
  • 79:43 - 79:46
    better because you think
    it's an actual treatment,
  • 79:46 - 79:50
    relative to the
    no-therapy group.
  • 79:50 - 79:52
    But the true therapy
    group where you actually
  • 79:52 - 79:54
    get treatment by
    physical therapist,
  • 79:54 - 79:59
    experiences the highest level
    of decrease in symptoms.
  • 80:00 - 80:02
    Is that good?
  • 80:02 - 80:05
    Sure.
  • 80:05 - 80:08
    Do you want to explain it
    in a different way, Rick?
  • 80:08 - 80:13
    No, I was definitely
    following you. For sure.
  • 80:13 - 80:17
    The placebo effect can
    still have effect,
  • 80:17 - 80:23
    but it doesn't mean
    it's still imaginary.
  • 80:23 - 80:27
    It's imaginary, but
    it's doing something.
  • 80:29 - 80:32
    This is another threat
    to internal validity.
  • 80:32 - 80:35
    Like all the other threats
    to internal validity,
  • 80:35 - 80:37
    including a comparison
    group, which in this case,
  • 80:37 - 80:41
    is a group that receives
    no therapy at all,
  • 80:41 - 80:42
    can help you see
    whether you have
  • 80:42 - 80:45
    a placebo effect or not.
  • 80:46 - 80:51
    We're done with
    this one for now,
  • 80:51 - 80:53
    we'll continue on Wednesday.
  • 80:55 - 80:59
    Let's go to the next
    PowerPoint. Oh, no.
  • 80:59 - 81:05
    Where is it? Let's see.
  • 81:05 - 81:11
    Do you guys have anything
    exciting coming up?
  • 81:12 - 81:14
    No.
  • 81:14 - 81:15
    No?
  • 81:16 - 81:19
    My birthday's this month.
  • 81:19 - 81:22
    I'm not going to do
    anything what can I do?
  • 81:22 - 81:27
    But last year for my boyfriend's
    birthday, he's vegan.
  • 81:27 - 81:29
    Well, he can't have dairy,
  • 81:29 - 81:33
    so we usually just get vegan
    cakes 'cause it's easier.
  • 81:33 - 81:35
    I made him Atres
    etches, vegan cake.
  • 81:35 - 81:37
    Do you guys Atres etches?
  • 81:37 - 81:40
    Oh, you should have
    it. It's really good.
  • 81:40 - 81:41
    It's basically three milks,
  • 81:41 - 81:44
    but it's usually like
    regular milk and
  • 81:44 - 81:46
    condensed milk and evaporated
    milk or something.
  • 81:46 - 81:49
    It's a cake that's
  • 81:49 - 81:52
    sort of very moist and
    has a lot of liquid,
  • 81:52 - 81:53
    and you dip it in the liquid and
  • 81:53 - 81:54
    it's so good and delicious.
  • 81:54 - 81:56
    Anyway, last year I made,
  • 81:56 - 81:58
    I'll send you or I'll show
    you a picture next time.
  • 81:58 - 82:02
    I made him a vegan Dzeches,
    which I just talked about.
  • 82:02 - 82:04
    It has three different milk.
  • 82:04 - 82:06
    I had to use, like,
    coconut milk and
  • 82:06 - 82:08
    almond milk and some other milk.
  • 82:08 - 82:11
    But it came out really good.
  • 82:11 - 82:13
    I might start practicing that.
  • 82:13 - 82:16
    For my birthday.
  • 82:16 - 82:19
    There might be a lot
    of cake in my life.
  • 82:19 - 82:21
    That's the most exciting
    thing going on so far.
  • 82:21 - 82:24
    Yeah. All right,
  • 82:24 - 82:27
    Haley, anything exciting
    coming up for you?
  • 82:28 - 82:33
    Um, it's my boyfriend's
    birthday this month, as well.
  • 82:33 - 82:36
    What are you going to do
    or when is his birthday?
  • 82:36 - 82:39
    The 14th.
  • 82:39 - 82:42
    We're probably just going
    to get sushi and hang out.
  • 82:42 - 82:44
    To go sushi now,
  • 82:44 - 82:46
    'cause the restaurants in
  • 82:46 - 82:49
    my county are shut
    back down again, so.
  • 82:49 - 82:53
    Yeah. Sushi is awesome.
  • 82:53 - 82:55
    I love sushi.
  • 82:55 - 82:56
    Yeah. I didn't have
    sushi until I was like,
  • 82:56 - 83:00
    22, because I was
    like, Oh, raw fish.
  • 83:00 - 83:02
    Then one of my friends is
    like, You have to try it.
  • 83:02 - 83:04
    So I did, and I'm
    like, Oh, my God.
  • 83:04 - 83:07
    Then when I went to UC Santa
    Barbara for my PhD, like,
  • 83:07 - 83:10
    I would have poke bowls
    multiple times a week.
  • 83:10 - 83:13
    Have you guys had a poke bowl?
  • 83:14 - 83:16
    I've had one once.
  • 83:16 - 83:17
    Oh, yeah. It's so good.
  • 83:17 - 83:19
    They don't have them
    as much in Oregon,
  • 83:19 - 83:24
    but in California,
    they had, of course,
  • 83:24 - 83:26
    everyone hates
    Californians, but they had,
  • 83:26 - 83:29
    like a subway poke bowl
    where you would be able to,
  • 83:29 - 83:30
    like, choose your
    grain and then choose,
  • 83:30 - 83:32
    like how much stuff
    you want in it.
  • 83:32 - 83:34
    That's what I miss. And
    now I want a poke bowl.
  • 83:34 - 83:38
    Okay, so let's talk about
    writing a method section.
  • 83:38 - 83:41
    Why we should write
    a method section?
  • 83:41 - 83:43
    One, you want to
    be able to write
  • 83:43 - 83:45
    a method section in
    case anyone wants
  • 83:45 - 83:52
    to do your study again
    or extend your study.
  • 83:52 - 83:53
    When I read your method section,
  • 83:53 - 83:55
    I should be able to say, Okay,
  • 83:55 - 84:01
    so Alesia measured extra
    version using this,
  • 84:01 - 84:05
    and then she measured anxiety
    symptoms measuring that.
  • 84:05 - 84:10
    I want to add in
    gender as a factor.
  • 84:10 - 84:14
    I'm going to use
    Alesia's method and
  • 84:14 - 84:15
    include gender as
    a factor to see if
  • 84:15 - 84:17
    I get similar results to her.
  • 84:17 - 84:19
    That's essentially
    what we're looking for
  • 84:19 - 84:21
    when we look at a
    method section.
  • 84:21 - 84:24
    The section will allow you
    to see who was recruited,
  • 84:24 - 84:27
    which affects the
    generalizability of your results,
  • 84:27 - 84:30
    how the variables
    were operationalized.
  • 84:30 - 84:34
    We measured loneliness using
    the UCLA loneliness scale,
  • 84:34 - 84:38
    for instance, and what the
    outcome measures were.
  • 84:38 - 84:41
    All of this method section
  • 84:41 - 84:43
    allows us to evaluate the
    strength of the study,
  • 84:43 - 84:47
    identify any confounds and
    extend existing research.
  • 84:47 - 84:49
    If I knew as
  • 84:49 - 84:53
    a soda researcher that coke
    people are more lonely,
  • 84:53 - 84:55
    I would want Rick to
  • 84:55 - 84:58
    measure whether people are
    Coke or Pepsi drinkers,
  • 84:58 - 85:00
    so we can address
  • 85:00 - 85:03
    that as a potential
    confound in the paper.
  • 85:03 - 85:05
    Okay.
  • 85:05 - 85:07
    How do you format
    your method section?
  • 85:07 - 85:09
    Again, like the
    rest of your paper,
  • 85:09 - 85:10
    you're going to use past tense.
  • 85:10 - 85:12
    At this point in your writing,
  • 85:12 - 85:14
    when we actually
    write the paper,
  • 85:14 - 85:15
    you would have already completed
  • 85:15 - 85:19
    the research topic,
    or research project.
  • 85:19 - 85:23
    Make sure to center the
    word method. No methods.
  • 85:23 - 85:25
    It's not methods, not plural.
  • 85:25 - 85:27
    It's singular method.
  • 85:27 - 85:29
    No bold, underline or italics.
  • 85:29 - 85:31
    Subheadings are flush left,
  • 85:31 - 85:33
    and italicized for
    participants materials,
  • 85:33 - 85:35
    procedure design and analyses.
  • 85:35 - 85:38
    Okay, what about
    the subheadings?
  • 85:38 - 85:39
    Participants,
  • 85:39 - 85:41
    how many participants
    do you want to recruit?
  • 85:41 - 85:44
    The rule of thumb is 50
    participants per cell.
  • 85:44 - 85:46
    What the hell is a cell? We'll
    see it on the next slide.
  • 85:46 - 85:48
    But that's changing,
    and it's unlikely that
  • 85:48 - 85:52
    you'll get approximately
    50 participants per cell.
  • 85:52 - 85:55
    We talked a little
    bit about power.
  • 85:55 - 85:58
    And in the last
    four to five years,
  • 85:58 - 86:03
    we've been under a lot of
    scrutiny as psychologists.
  • 86:03 - 86:05
    We've created different kind of
  • 86:05 - 86:07
    statistical techniques
    that allow us to say,
  • 86:07 - 86:09
    if we want to make
    sure that we have
  • 86:09 - 86:11
    less than a 5% chance or
  • 86:11 - 86:16
    5% rate of getting results
    that are due to chance,
  • 86:16 - 86:20
    then we must recruit at
    least 190 participants.
  • 86:20 - 86:23
    But before that, people
    were like, Okay,
  • 86:23 - 86:25
    you can get 50
    participants per cell,
  • 86:25 - 86:29
    which will be on the next slide.
  • 86:29 - 86:31
    Let's say that my
    research question is to
  • 86:31 - 86:34
    investigate how music affects
    athletic performance.
  • 86:34 - 86:36
    Music is an
    independent variable,
  • 86:36 - 86:39
    and athletic performance
    is a dependent variable.
  • 86:39 - 86:42
    Then I have my participants
  • 86:42 - 86:46
    listen to a specific
    kind of music.
  • 86:46 - 86:49
    Independent variables music.
  • 86:49 - 86:51
    Yes, and the independent
    variable has
  • 86:51 - 86:54
    two levels, techno or classical.
  • 86:54 - 86:57
    I have one dependent variable
    of athletic performance,
  • 86:57 - 87:00
    and we base the sample size
    off of the levels of the IV.
  • 87:00 - 87:05
    One cell means one
    level of the IV.
  • 87:05 - 87:06
    Because you have one
  • 87:06 - 87:08
    independent variable
    with two levels,
  • 87:08 - 87:10
    techno or classical music,
  • 87:10 - 87:13
    you would need 100 participants.
  • 87:13 - 87:18
    I think I have um a
    graph on the next slide.
  • 87:18 - 87:24
    Okay. Do those numbers
    track for you?
  • 87:24 - 87:27
    Yeah. Okay, so let's say that
  • 87:27 - 87:29
    I also want to look at gender.
  • 87:29 - 87:32
    I categorize people as
    either male or female.
  • 87:32 - 87:35
    Now I have two independent
    variables, music and gender.
  • 87:35 - 87:37
    Music still has two levels,
  • 87:37 - 87:38
    techno classical,
  • 87:38 - 87:41
    and gender has two
    levels, male or female.
  • 87:41 - 87:43
    Now we have four cells.
  • 87:43 - 87:44
    We still have one dependent
  • 87:44 - 87:46
    variable athletic performance,
  • 87:46 - 87:48
    and we base a sample size off of
  • 87:48 - 87:50
    the number of and
    levels of the IV.
  • 87:50 - 87:53
    Thus we would need 200
    participants in my study.
  • 87:53 - 87:56
    This is what I'm talking
    about when I say cells.
  • 87:57 - 87:59
    Hey, this is going
    to be like yours.
  • 87:59 - 88:01
    You're going to have
    male and female,
  • 88:01 - 88:05
    and then here you're going
    to have the two age groups.
  • 88:05 - 88:08
    You would need about
    200 participants.
  • 88:11 - 88:13
    Does that make sense?
  • 88:13 - 88:14
    Yes.
  • 88:14 - 88:17
    You'd have males in
    their 20s and males
  • 88:17 - 88:18
    in whatever the
    other age group is,
  • 88:18 - 88:20
    and then you'd have
    females in their 20s and
  • 88:20 - 88:23
    females in whatever the
    other age group is.
  • 88:23 - 88:25
    Alesia, you only
  • 88:25 - 88:29
    have one independent
    variable with two levels.
  • 88:29 - 88:31
    How many participants
    would you need?
  • 88:33 - 88:35
    A hundred.
  • 88:35 - 88:37
    Yep, Rick.
  • 88:37 - 88:39
    One hundred.
  • 88:39 - 88:41
    Yeah. Great.
  • 88:41 - 88:46
    Yeah, so let's just pretend
    this and this is yours Rick.
  • 88:46 - 88:48
    So all people measure
  • 88:48 - 88:51
    loneliness and then we
  • 88:51 - 88:54
    have people pre COVID
    and post COVID,
  • 88:54 - 88:56
    so you would only
    need 100 people.
  • 88:57 - 89:00
    Okay, all right.
  • 89:00 - 89:03
    So that's just
    about participants.
  • 89:03 - 89:06
    I want your number
    of participants,
  • 89:06 - 89:08
    I also want any
    screening criteria.
  • 89:08 - 89:13
    Are there any criteria that
    you're using to screen them?
  • 89:13 - 89:14
    Are you making sure that
  • 89:14 - 89:17
    they aren't
    clinically depressed?
  • 89:17 - 89:19
    Alisia, are you
    making sure that they
  • 89:19 - 89:21
    all have diagnosed anxiety?
  • 89:21 - 89:22
    Because it would suck if
  • 89:22 - 89:24
    you had introverts
    and extroverts,
  • 89:24 - 89:26
    but then none of
    them had anxiety,
  • 89:26 - 89:27
    so how are you going to measure
  • 89:27 - 89:29
    differences in anxiety symptoms?
  • 89:29 - 89:33
    So your screening criteria
    might be that they have
  • 89:33 - 89:35
    anxiety or have been
  • 89:35 - 89:38
    diagnosed with anxiety
    at some point.
  • 89:38 - 89:40
    Haley, yours might be
    that they're actual
  • 89:40 - 89:43
    working professional in
    those fields, right?
  • 89:43 - 89:45
    Yeah.
  • 89:45 - 89:46
    Yeah. So you would be recruiting
  • 89:46 - 89:48
    what kind of people,
    like business people?
  • 89:48 - 89:53
    I think so. Yeah. I
    need to think about how
  • 89:53 - 89:56
    to operationalize
  • 89:56 - 90:00
    leadership positions
    like from [OVERLAPPING]
  • 90:00 - 90:03
    You're good for the start.
    So you will randomly
  • 90:04 - 90:13
    select five or 10 of
    the top 50 Forbes,
  • 90:13 - 90:18
    whatever, money making
    [LAUGHTER] companies
  • 90:18 - 90:20
    and survey CEOs and
  • 90:20 - 90:23
    COOs and other leadership
    positions there.
  • 90:23 - 90:25
    So you're going to
    randomly select
  • 90:25 - 90:27
    some of the businesses
    and then you're going
  • 90:27 - 90:29
    to grab some of the participants
  • 90:29 - 90:33
    from those randomly
    selected businesses.
  • 90:35 - 90:37
    Just aim for the moon
    because you're not
  • 90:37 - 90:39
    really going to do it and
    if you want to do it,
  • 90:39 - 90:43
    you probably can next
    year, but we'll see.
  • 90:43 - 90:44
    Okay.
  • 90:44 - 90:47
    Okay. Then you'll also
    include basic demographics.
  • 90:47 - 90:48
    So are they all WOU students?
  • 90:48 - 90:54
    Are they all in the
    top 50 Forbes list?
  • 90:54 - 90:55
    I also want you to tell me about
  • 90:55 - 90:57
    their age, their gender, race,
  • 90:57 - 90:59
    ethnicity, any other variables
  • 90:59 - 91:01
    you think might be interesting.
  • 91:01 - 91:04
    You can also include
    information if it's relevant.
  • 91:04 - 91:06
    So income levels might
  • 91:06 - 91:08
    be relevant if you're
    studying the effects
  • 91:08 - 91:09
    of helping people or
  • 91:09 - 91:12
    helping behavior on
    monetary donations.
  • 91:12 - 91:16
    yeah. So we did a study
  • 91:16 - 91:19
    with professionals that
    make a lot of money,
  • 91:19 - 91:24
    and we're like, we're
    offering to pay them $50.
  • 91:24 - 91:27
    But they make so much money,
    why don't they donate?
  • 91:27 - 91:29
    Do you think they donated?
  • 91:29 - 91:36
    No. These people took
    their $50 gift cards,
  • 91:36 - 91:39
    which is fine, but they
    make so much money.
  • 91:39 - 91:41
    So we actually came up with
  • 91:41 - 91:43
    four different
    charities that we all
  • 91:43 - 91:45
    support and we like
  • 91:45 - 91:47
    painstakingly wrote
    the descriptions
  • 91:47 - 91:48
    of each charity and we're like,
  • 91:48 - 91:50
    you can donate to one
    of these four charities
  • 91:50 - 91:52
    or click the last button.
  • 91:52 - 91:54
    To scroll and click
    the last button
  • 91:54 - 91:55
    if you want the gift card to
  • 91:55 - 91:59
    yourself and the like 98%
    gave it to themselves,
  • 91:59 - 92:01
    but income levels
    might be different.
  • 92:01 - 92:03
    So maybe if we
    recruited students
  • 92:03 - 92:05
    and we could see
    whether students are
  • 92:05 - 92:07
    more likely to give
    donations relative
  • 92:07 - 92:11
    to working professionals,
    that would be interesting.
  • 92:11 - 92:13
    But that might not be
    interesting for your study.
  • 92:13 - 92:15
    But income levels
    might be irrelevant
  • 92:15 - 92:18
    if you're studying
    coffee consumption,
  • 92:18 - 92:19
    or maybe not if you're
  • 92:19 - 92:21
    looking at how many times
    people go to Starbucks.
  • 92:21 - 92:23
    I also want numbers.
  • 92:23 - 92:27
    So were any people excluded
    from analyses and why,
  • 92:27 - 92:31
    you can just, Alisia, you
    can make something up.
  • 92:31 - 92:34
    You can say something like
    I excluded 10 participants
  • 92:34 - 92:36
    because they did not
  • 92:36 - 92:39
    complete the anxiety
    symptom questionnaire.
  • 92:39 - 92:41
    ErricTingle, you
    could say something
  • 92:41 - 92:44
    like people did not complete
  • 92:44 - 92:47
    the UCLA loneliness scale
  • 92:47 - 92:50
    and I had to delete
    them from the data.
  • 92:50 - 92:53
    So for demographics, we
    usually include percent
  • 92:53 - 92:56
    of male versus female,
    their age range.
  • 92:56 - 92:59
    So participants were between
    the ages of 18 and 30.
  • 92:59 - 93:05
    The mean average age was 24
    and the standard deviation.
  • 93:05 - 93:07
    Where were the
    participants recruited?
  • 93:07 - 93:10
    So Haley, maybe you sent
  • 93:10 - 93:13
    an email inviting them to
    complete a Qual trix survey,
  • 93:13 - 93:16
    or maybe it was post COVID and
  • 93:16 - 93:18
    you went to one of
    the conferences where
  • 93:18 - 93:21
    the top business leaders go and
  • 93:21 - 93:23
    you caught people as they were
  • 93:23 - 93:24
    on their way to
    lunch and had them
  • 93:24 - 93:26
    complete a really fast survey.
  • 93:26 - 93:30
    Were they compensated, and
    if they were compensated,
  • 93:30 - 93:31
    were they compensated
    with course credit
  • 93:31 - 93:33
    or monetary incentives.
  • 93:33 - 93:35
    Most of the time,
    especially in 467,
  • 93:35 - 93:38
    468, you'll compensate
    them with course credit.
  • 93:38 - 93:41
    Participants completed the study
  • 93:41 - 93:43
    for half of course credit.
  • 93:43 - 93:46
    For the subsection
    of the materials,
  • 93:46 - 93:49
    all materials used in this
    study should be mentioned.
  • 93:49 - 93:51
    So for example, the
    Beck Depression
  • 93:51 - 93:53
    inventory and cite
    it appropriately.
  • 93:53 - 93:55
    Rick, you're going to have
  • 93:55 - 93:58
    the UCLA loneliness
    scale and cite it.
  • 93:58 - 94:01
    Which measures did
    you decide on?
  • 94:01 - 94:04
    Why? Why did you decide on
    the UCLA loneliness scale?
  • 94:04 - 94:06
    You can say it has
    good reliability.
  • 94:06 - 94:08
    It's been tested across
    different samples.
  • 94:08 - 94:09
    It has good validity,
  • 94:09 - 94:11
    and it has good reliability.
  • 94:11 - 94:14
    It could just be a
    sentence about that.
  • 94:14 - 94:16
    If the surveys are used,
  • 94:16 - 94:18
    please describe the survey.
  • 94:18 - 94:21
    So a short description of
    measure and what it measures.
  • 94:21 - 94:24
    So the UCLA loneliness
    scale measures
  • 94:24 - 94:28
    loneliness among young adults.
  • 94:28 - 94:33
    It has 10 items, I'm
    just making this up,
  • 94:33 - 94:34
    and it is a Likert scale where
  • 94:34 - 94:36
    participants answer items like,
  • 94:36 - 94:39
    I am a lonely person
    on a scale from
  • 94:39 - 94:43
    one strongly disagree to
    seven, strongly agree.
  • 94:44 - 94:47
    People who score high
    on the loneliness scale
  • 94:47 - 94:49
    tend to be more
    lonely than those who
  • 94:49 - 94:51
    score low on the
    loneliness scale.
  • 94:51 - 94:54
    So what does a high or low
    score on the scale mean?
  • 94:54 - 94:57
    You should include
    sample questions.
  • 94:57 - 95:00
    So like I just did, I
    am a lonely person,
  • 95:00 - 95:03
    from strongly disagree
    to strongly agree.
  • 95:03 - 95:07
    Talk about the
    reliability, the validity.
  • 95:08 - 95:10
    I want you to include all items
  • 95:10 - 95:12
    from the original
    measure in the appendix.
  • 95:12 - 95:15
    So you will have an appendix
    at the end of your paper,
  • 95:15 - 95:18
    and right there I just want
    you to type up the measures.
  • 95:18 - 95:20
    When using a pre existing
    published measure
  • 95:20 - 95:22
    which you all should be using,
  • 95:22 - 95:24
    I want you to include
    the full name
  • 95:24 - 95:25
    of the measure followed by
  • 95:25 - 95:28
    an abbreviation and citation
    of the original author.
  • 95:28 - 95:31
    So one index that I
  • 95:31 - 95:34
    use a lot is the suspicions
    of motives index,
  • 95:34 - 95:39
    and we shorten it by calling
    it SOMI then I cite it.
  • 95:39 - 95:41
    So full name of measure,
  • 95:41 - 95:44
    abbreviation, and citation
    of the original paper.
  • 95:44 - 95:46
    After that, you don't
    have to call it
  • 95:46 - 95:48
    the suspicion of motives
    index throughout
  • 95:48 - 95:52
    the rest of your method
    or results section.
  • 95:52 - 95:54
    You can just call it SOMI.
  • 95:56 - 95:59
    So let me look up a paper
  • 95:59 - 96:06
    because this is all
    sort of, hold on.
  • 96:08 - 96:11
    Like, I'm just speaking
    and it might not make
  • 96:11 - 96:13
    complete sense and I'm just
  • 96:13 - 96:14
    thinking of me as a
    student and I'd be like,
  • 96:14 - 96:16
    okay, that's great, but how
  • 96:16 - 96:18
    is it going to look
    like in my paper?
  • 96:24 - 96:29
    Can you guys see
    my search screen?
  • 96:29 - 96:30
    No.
  • 96:30 - 96:30
    No. Okay.
  • 96:30 - 96:34
    [inaudible].
  • 96:34 - 96:35
    I can't.
  • 96:44 - 96:48
    Okay. Share.
  • 96:50 - 96:54
    Cool. Can you see
    this paper now?
  • 96:57 - 97:00
    This is one of my papers.
  • 97:00 - 97:02
    This is a short paper,
  • 97:02 - 97:05
    so you can use it to
    look at the method.
  • 97:05 - 97:09
    For instance, method,
    subjects in design,
  • 97:09 - 97:14
    186 Latino students
    participated for $5.
  • 97:14 - 97:16
    You don't have to conclude
    this effect size.
  • 97:16 - 97:18
    This was a headache,
    because they made
  • 97:18 - 97:20
    me rewrite the paper
    and include that.
  • 97:20 - 97:23
    This is a power thing that
    I was talking to you about.
  • 97:23 - 97:25
    We set a goal of 45
    participants per
  • 97:25 - 97:28
    condition and stopped when
    that number was reached.
  • 97:28 - 97:31
    There's a new thing
    that we have to do.
  • 97:31 - 97:34
    Seven participants didn't
    complete the PEMS.
  • 97:34 - 97:35
    Ten failed to indicate that
  • 97:35 - 97:37
    the Latino candidate was hired,
  • 97:37 - 97:38
    and six did not
    complete the Stroop.
  • 97:38 - 97:42
    Thus, the final sample was 163.
  • 97:42 - 97:44
    The average age was this.
  • 97:44 - 97:46
    We had 118 women,
  • 97:46 - 97:48
    44 men, and one person
    who did not report.
  • 97:48 - 97:52
    The procedures, they received
    an email invitation to
  • 97:52 - 97:56
    participate for pay and
    provided informed consent.
  • 97:56 - 97:58
    Study A involved reviewing
  • 97:58 - 98:00
    and evaluating recent
    recommendations.
  • 98:00 - 98:02
    Study B measured
    cognitive performance.
  • 98:02 - 98:04
    This study was conducted
    in compliance with
  • 98:04 - 98:06
    the Campus Institutional
    Review Board.
  • 98:06 - 98:09
    Participants were randomly
    assigned to conditions.
  • 98:09 - 98:12
    Then I talk about the
    random assignments
  • 98:12 - 98:15
    , so candidate qualifications.
  • 98:15 - 98:19
    People either saw a
    job description for
  • 98:19 - 98:21
    an entry level human
    resources position
  • 98:21 - 98:23
    followed by the resumes of
  • 98:23 - 98:26
    one Latino male and two
    white male candidates.
  • 98:26 - 98:27
    The race and gender
    of the candidates
  • 98:27 - 98:29
    were manipulated
    based on the names,
  • 98:29 - 98:31
    based on their resumes.
  • 98:31 - 98:32
    One was clearly the
    best qualified,
  • 98:32 - 98:35
    one was the worst, and the
    third was in the middle.
  • 98:35 - 98:37
    For half of the participants,
  • 98:37 - 98:39
    the best qualified
    candidate was Latino.
  • 98:39 - 98:40
    For the other half,
  • 98:40 - 98:43
    the moderately qualified
    candidate was Latino.
  • 98:43 - 98:46
    The worst qualified
    candidate was always white.
  • 98:47 - 98:49
    After viewing all the resumes,
  • 98:49 - 98:53
    participants saw the human
    resources officer's profile,
  • 98:53 - 98:54
    indicated his race and gender,
  • 98:54 - 98:56
    and read comments
    about each candidate.
  • 98:56 - 99:00
    They read what they said
    about each candidate and
  • 99:00 - 99:03
    then I also manipulated
    the diversity rationale.
  • 99:03 - 99:05
    Whether we said that the person
  • 99:05 - 99:06
    would add diversity
    to the company or
  • 99:06 - 99:10
    not and then I add
    manipulation checks,
  • 99:10 - 99:12
    but this is what you would have
  • 99:12 - 99:13
    with your dependent measures.
  • 99:13 - 99:16
    For me, it was cognitive
    performance on the Stroop task.
  • 99:16 - 99:20
    You guys remember the Stroop
    task where it's like,
  • 99:20 - 99:24
    it has the word blue,
    but it's in red.
  • 99:25 - 99:27
    You have to say the name of
    the word and not the color
  • 99:27 - 99:31
    , so that's what I used.
  • 99:31 - 99:34
    You can see my method
    section is very short.
  • 99:34 - 99:39
    I should be maybe
    one or two pages.
  • 99:39 - 99:45
    For instance, 100 participants
  • 99:45 - 99:48
    at 100 students at
  • 99:48 - 99:51
    a public university participated
  • 99:51 - 99:53
    online for course credit.
  • 99:53 - 99:54
    This could be your study, Rick.
  • 99:54 - 99:56
    Previous studies, we don't.
  • 99:56 - 99:59
    All of this is trash.
    You don't need this.
  • 99:59 - 100:03
    You can say seven
    participants didn't
  • 100:03 - 100:07
    complete the
    loneliness scale thus,
  • 100:07 - 100:11
    our final sample was
    93 participants.
  • 100:11 - 100:14
    You can just flub the
    numbers for the age,
  • 100:14 - 100:17
    how many women
    versus how many men.
  • 100:17 - 100:20
    Procedure, participants received
  • 100:20 - 100:21
    an email invitation to
  • 100:21 - 100:24
    participate in the
    study for course credit
  • 100:24 - 100:29
    and they were asked to complete
  • 100:29 - 100:34
    surveys regarding
    their experiences
  • 100:34 - 100:36
    in the last few years.
  • 100:36 - 100:39
    Participants were randomly
    assigned to one of
  • 100:39 - 100:45
    two conditions and then you
    can say COVID manipulation.
  • 100:45 - 100:49
    Participants saw a
    description page
  • 100:49 - 100:50
    that either said that they would
  • 100:50 - 100:53
    be answering questions related
  • 100:53 - 100:56
    to their experiences
    before COVID,
  • 100:56 - 100:58
    or they were asked
  • 100:58 - 101:02
    to write their
    experiences after COVID.
  • 101:02 - 101:09
    Then that'll be your
    whole manipulation here.
  • 101:09 - 101:13
    Your dependent measure
    will be loneliness,
  • 101:13 - 101:16
    so dependent measure
    UCLA loneliness scale.
  • 101:16 - 101:21
    The UCLA loneliness scale was
    used to measure loneliness.
  • 101:21 - 101:24
    Participants answered
    these questions on
  • 101:24 - 101:30
    a one strongly disagree to
    seven strongly agree scale,
  • 101:30 - 101:34
    and that's basically
    your method section.
  • 101:35 - 101:37
    Does it make more
    sense now that I'm
  • 101:37 - 101:39
    putting it in an actual paper?
  • 101:39 - 101:40
    Yes.
  • 101:40 - 101:41
    Yes.
  • 101:41 - 101:43
    This paper took me
    forever to write.
  • 101:43 - 101:47
    I will tell you, I hate
    writing. It's hard.
  • 101:47 - 101:52
    It is really hard and I
    completely understand all of you.
  • 101:53 - 101:56
    We have 6 minutes left, God.
  • 101:56 - 101:59
    Step by step of how you
    collected the data.
  • 101:59 - 102:01
    This is a recipe.
  • 102:01 - 102:03
    I want you to mix your
    water, your flour and yeast,
  • 102:03 - 102:06
    add salt, let the bread
    rise overnight, et cetera.
  • 102:06 - 102:08
    Make sure to include
    enough details,
  • 102:08 - 102:09
    so another researcher
    could replicate
  • 102:09 - 102:13
    your study where were your
    surveys completed online,
  • 102:13 - 102:14
    in person in a classroom.
  • 102:14 - 102:17
    Was there a research
    assistant present and so on.
  • 102:18 - 102:21
    Again, the procedure right
  • 102:21 - 102:22
    in the order the
    events occurred.
  • 102:22 - 102:23
    I said I emailed them a survey,
  • 102:23 - 102:26
    they clicked on the link, blah.
  • 102:26 - 102:28
    Usually you start with
    informed consent.
  • 102:28 - 102:30
    You discuss the
    experimental design,
  • 102:30 - 102:31
    you discuss the conditions,
  • 102:31 - 102:34
    how the students were
    assigned to condition.
  • 102:34 - 102:36
    When did the
    experiment take place?
  • 102:36 - 102:37
    What were the instructions to
  • 102:37 - 102:40
    the participants and
    did you deceive them?
  • 102:40 - 102:41
    Then if you deceive them,
  • 102:41 - 102:44
    did you include debriefing?
  • 102:44 - 102:47
    Your method should only
  • 102:47 - 102:49
    be about a page to
    two pages long.
  • 102:49 - 102:53
    Very short. You can use
    my paper as a sample.
  • 102:53 - 102:57
    I also included
    another sample paper,
  • 102:57 - 103:01
    so let me open the link.
  • 103:06 - 103:09
    That paper was only
    five or six pages long,
  • 103:09 - 103:14
    but it took me a long
    time to get it done.
  • 103:14 - 103:20
    This is the link that's
    included in your PowerPoint.
  • 103:20 - 103:23
    No I already have it posted
    without the questions.
  • 103:23 - 103:25
    You'll write an abstract later,
  • 103:25 - 103:28
    but most of you have used this.
  • 103:28 - 103:30
    I can get everyone
    in class right now,
  • 103:30 - 103:34
    use the thing I gave them,
    the little template.
  • 103:34 - 103:38
    That's the intro. The
    method, here it is.
  • 103:38 - 103:41
    Your participant, describes who
  • 103:41 - 103:44
    should be in your study,
    the research design.
  • 103:45 - 103:49
    We can talk about that
    also on Wednesday.
  • 103:49 - 103:56
    The measures, which ones
    you used and procedure.
  • 103:56 - 104:02
    That's it. I also
    included another paper,
  • 104:02 - 104:06
    I believe with a Purdue Owl.
  • 104:14 - 104:19
    I've been using the Purdue
    Owl since I was an undergrad.
  • 104:20 - 104:23
    I would also use this.
  • 104:23 - 104:28
    They have sample papers.
  • 104:33 - 104:36
    No, I hate how small this is.
  • 104:47 - 104:49
    They did a literature review.
  • 104:49 - 104:53
    All of this sucks. That
    would not be good.
  • 104:53 - 104:56
    One to model. I think
    this one has data.
  • 105:13 - 105:16
    This also has a metanalysis,
    so that might not be good.
  • 105:16 - 105:20
    Any of the papers
    that you found for
  • 105:20 - 105:22
    your review should
    also be good for
  • 105:22 - 105:25
    this to model after. Let's see.
  • 105:25 - 105:32
    Sure. This is another short
    paper, one of my favorites.
  • 105:33 - 105:38
    Their procedure was just that.
  • 105:40 - 105:44
    I can also upload
    another paper onto
  • 105:44 - 105:48
    our Canvas page so
  • 105:48 - 105:52
    that you get a sense of
    how to write a paper.
  • 105:52 - 105:56
    Let's see. I think I
    already have some.
  • 106:10 - 106:17
    Here we go. There you go.
  • 106:17 - 106:21
    Method, participants procedure,
  • 106:21 - 106:25
    measures. It could
    just be a page.
  • 106:25 - 106:28
    It's already in our Canvas page.
  • 106:28 - 106:29
    You can start
    writing your method
  • 106:29 - 106:33
    today or whenever you want.
  • 106:34 - 106:39
    That was a lot. Do you all
    have any questions, comments?
  • 106:40 - 106:44
    Is this portion
    of the paper due,
  • 106:44 - 106:47
    is it next week or
    the week after?
  • 106:47 - 106:49
    It's next.
  • 106:49 - 106:52
    This portion of the paper
    is due on the 16th.
  • 106:53 - 107:00
    Not this Sunday but
    next Sunday. Sorry.
  • 107:00 - 107:04
    It's not due. Well, I'm
    still going to do it now.
  • 107:05 - 107:08
    I'm giving y'all a lot of time
  • 107:08 - 107:10
    to be able to write this.
    It's not just this.
  • 107:10 - 107:11
    It's going to be the
    results section,
  • 107:11 - 107:14
    and we'll talk about the
    results section on Thursday,
  • 107:14 - 107:16
    but that should also
    be relatively short
  • 107:16 - 107:19
    because you don't
    have any results.
  • 107:19 - 107:22
    I just want you to tell me
    what analysis you would run.
  • 107:22 - 107:25
    We'll talk about that
    on Thursday as well.
  • 107:25 - 107:27
    The method will be about a page.
  • 107:27 - 107:29
    Results will be
    maybe half a page.
  • 107:29 - 107:32
    Discussion will maybe be
    between one and three pages,
  • 107:32 - 107:35
    and we'll go over the
    discussion on Monday.
  • 107:35 - 107:38
    Before this Sunday, we
  • 107:38 - 107:41
    will have gone over
    method, results,
  • 107:41 - 107:43
    and then you should
    work on that over
  • 107:43 - 107:44
    the weekend, and then on Monday,
  • 107:44 - 107:46
    we'll talk about the discussion,
  • 107:46 - 107:47
    and then you'll have the
    entire week to work on
  • 107:47 - 107:51
    the discussion in the IRB.
  • 107:51 - 107:53
    You have two weeks.
    Get started on it now.
  • 107:53 - 107:55
    I'm also a procrastinator.
  • 107:55 - 107:59
    I understand. I'm the worst.
  • 107:59 - 108:02
    I'm giving you way
    more than enough time.
  • 108:02 - 108:03
    Let's just look
    ahead really quick.
  • 108:03 - 108:04
    I know it's already time, but
  • 108:04 - 108:10
    I'm trying to give you ample
    time to be able to get
  • 108:10 - 108:13
    this done and look for
    examples and think
  • 108:13 - 108:17
    about it before we actually
    have to write the paper.
  • 108:17 - 108:20
    We're almost done with lectures,
  • 108:20 - 108:21
    but I do want you all
  • 108:21 - 108:23
    to try to schedule
    appointments with me to
  • 108:23 - 108:25
    review your papers because
    I want everyone to
  • 108:25 - 108:28
    get any of this
    class if you can.
  • 108:28 - 108:35
    We're Week 7. Next week is
    the last week of lecture.
  • 108:37 - 108:40
    The paper must include
    revised introduction.
  • 108:40 - 108:43
    You should already be working
    on that, your method, page,
  • 108:43 - 108:45
    results and data
    analysis strategy,
  • 108:45 - 108:49
    half a page, discussion,
    maybe three pages.
  • 108:49 - 108:51
    We'll also talk about the IRB,
  • 108:51 - 108:55
    very easy solve that
    we'll be due on the 16th.
  • 108:55 - 108:59
    Then you'll just have
    P quizzes next Sunday.
  • 108:59 - 109:02
    That'll be the end.
    Then you'll have
  • 109:02 - 109:07
    1-3 weeks to write
    your final paper.
  • 109:07 - 109:10
    I'll get your
    papers on the 16th.
  • 109:10 - 109:14
    I'll try to get it back
    to you by the 30th.
  • 109:14 - 109:17
    Then you just have to make
    minor edits depending on
  • 109:17 - 109:20
    how much feedback I give you,
  • 109:20 - 109:22
    and then you just have
  • 109:22 - 109:26
    the final exam and
    submit your final paper.
  • 109:26 - 109:30
    But you'll have two weeks
    of no classes with me,
  • 109:30 - 109:31
    and I want you to
    use that time to
  • 109:31 - 109:33
    meet with Writing Center tutors,
  • 109:33 - 109:36
    meet with me, make appointments.
  • 109:37 - 109:41
    I hope that will be enough
    time for you all to manage.
  • 109:41 - 109:44
    You'll really like
    me, then, because
  • 109:44 - 109:47
    we won't have to go over
    all these lectures.
  • 109:47 - 109:50
    The exam will open at 6:00 AM on
  • 109:50 - 109:53
    6/7 and closes on
    6/10 at 11:59 PM.
  • 109:53 - 109:57
    You have three days to take it.
  • 109:57 - 109:59
    It'll be two hours long.
  • 109:59 - 110:01
    You can choose any
    two-hour block
  • 110:01 - 110:02
    between those three
    days to take it.
  • 110:02 - 110:05
    It will cover all
    of the chapters.
  • 110:05 - 110:08
    Basically the questions
    I've been asking you,
  • 110:08 - 110:10
    I think will be on
    the exam, hint hint.
  • 110:10 - 110:13
    You can use any PowerPoints
  • 110:13 - 110:15
    that we have, you
    can use any PDFs,
  • 110:15 - 110:17
    you can use anything
    on the website,
  • 110:17 - 110:20
    you can use a text,
    but don't Google.
  • 110:20 - 110:22
    I can tell when you
    Google and you copy.
  • 110:22 - 110:24
    I've had that happen
    before, and no.
  • 110:24 - 110:26
    Just try to explain
    it in your own words.
  • 110:26 - 110:28
    That's why I try to have
    you explain things back to
  • 110:28 - 110:31
    me because if you
    can do that now,
  • 110:31 - 110:34
    you're going to be able
    to do that on the exam.
  • 110:36 - 110:38
    We're almost done
    with this class.
  • 110:38 - 110:43
    It's going by really
    quick. But you guys,
  • 110:43 - 110:46
    at least your papers
    have been really good.
  • 110:46 - 110:48
    I gave good feedback, I hope,
  • 110:48 - 110:50
    and you're working on it,
  • 110:50 - 110:52
    and I look forward to
    seeing your second drafts.
  • 110:52 - 110:54
    If you need help, let me know,
  • 110:54 - 110:56
    but I think the intro is one
  • 110:56 - 110:57
    of the hardest parts to write.
  • 110:57 - 111:00
    The method and the
    results should be easy.
  • 111:00 - 111:04
    Any other questions or concerns?
  • 111:05 - 111:08
    I was wondering if
    I could talk to you
  • 111:08 - 111:10
    about the scales that
  • 111:10 - 111:13
    I could potentially use because
    I have a couple in mind,
  • 111:13 - 111:15
    but I want to
  • 111:15 - 111:17
    make sure that I'm using
    the right scales, I guess.
  • 111:17 - 111:20
    Sure. If no one
    else has questions,
  • 111:20 - 111:25
    y'all can skedaddle, and
    I will meet with Alicia.
  • 111:25 - 111:28
    I guess I'll email
  • 111:28 - 111:32
    you and ask about the
    loneliness scale.
  • 111:32 - 111:34
    If you can just send me a link.
  • 111:34 - 111:37
    I'll just send it
    to you right now.
  • 111:37 - 111:41
    That'd be great. That's
    why I brought it up.
  • 111:42 - 111:44
    Please email me if you
    want help with that.
  • 111:44 - 111:47
    I don't want you wasting
    two hours of your life.
  • 111:47 - 111:49
    Thanks. I know it's frustrating.
  • 111:49 - 111:50
    I knew I shouldn't do it,
  • 111:50 - 111:53
    but I'm glad I looked up
    to see what time it was.
  • 111:55 - 111:57
    I have a lot of years of
  • 111:57 - 111:59
    experience banging my
    head against a wall,
  • 111:59 - 112:01
    trying to figure
    these things out.
  • 112:01 - 112:05
    Use my experience. Here we go.
  • 112:05 - 112:08
    I'm also unsure about
  • 112:08 - 112:12
    what scales I should
    use with mine, I guess.
  • 112:13 - 112:16
    Rick, I'm going to send
    this to you right now.
  • 112:16 - 112:21
    Alicia, I just have
    30 emails now.
  • 112:22 - 112:25
    Well, then I'm good.
    I appreciate it.
  • 112:25 - 112:28
    I'm going to get started on it.
  • 112:28 - 112:30
    Thanks for your great class.
  • 112:30 - 112:31
    It helps. I'm out.
  • 112:31 - 112:33
    Thank you.
  • 112:34 - 112:37
    Bye.
  • 112:37 - 112:41
    I'm going to share
    my Google screen.
  • 112:41 - 112:44
    Just ignore my emails.
    It's a headache.
  • 112:44 - 112:49
    Oh my God. Alicia,
  • 112:49 - 112:51
    you have an idea of
    some of the scales.
  • 112:51 - 112:54
    Haley, do you have an idea
    of some of your scales?
  • 112:54 - 112:57
    Not really. No, not yet.
  • 112:58 - 113:00
    Alicia.
  • 113:00 - 113:03
    You said you had an idea, so.
  • 113:03 - 113:07
    Yeah, so like some of the
    ones that I found in,
  • 113:07 - 113:10
    like, my reference
    articles seem good.
  • 113:10 - 113:13
    Like for personality, like,
  • 113:13 - 113:17
    the Eysenck I think let's see,
  • 113:17 - 113:19
    let me look at what it was.
  • 113:19 - 113:21
    Well, there's two that I
    could potentially use.
  • 113:21 - 113:24
    There's the Eysenck
    personality questionnaire,
  • 113:24 - 113:29
    and then there's the 10
    item personality inventory,
  • 113:29 - 113:32
    which that one's a lot shorter.
  • 113:32 - 113:36
    Do they both measure
    extraversion?
  • 113:36 - 113:39
    Yeah, I think they both.
  • 113:40 - 113:43
    I think they both measure,
  • 113:43 - 113:48
    all personality like all big
    five personality traits.
  • 113:48 - 113:52
    But I don't know if I want
    to use, like, I know,
  • 113:52 - 113:54
    I think you mentioned it
    once before where it's like,
  • 113:54 - 113:56
    I don't want my participants
  • 113:56 - 113:58
    necessarily to know
    what I'm measuring.
  • 113:58 - 114:00
    Like, having at least,
  • 114:00 - 114:03
    like, one other like,
  • 114:03 - 114:04
    personality trait
    might be helpful,
  • 114:04 - 114:08
    but I don't know how much
    is too much, I guess.
  • 114:08 - 114:11
    Yeah. How long is the Eysenck?
  • 114:12 - 114:19
    It is let's see.
    I think it's 48.
  • 114:19 - 114:22
    Yeah. I would just say that you
  • 114:22 - 114:27
    used part of the Eysenck
    to measure extraversion,
  • 114:27 - 114:31
    conscientiousness
    and agreeableness
  • 114:31 - 114:33
    or something like that.
  • 114:33 - 114:36
    To mask the true
    purpose of your study
  • 114:36 - 114:38
    and then talk about each
    of the sub measures.
  • 114:38 - 114:42
    Extraversion was measured
    by asking questions like,
  • 114:42 - 114:43
    whatever the questions are,
  • 114:43 - 114:45
    agreeable illness
    was measured by
  • 114:45 - 114:47
    using whatever the
    questions are,
  • 114:47 - 114:50
    and then the other one,
    conscientiousness.
  • 114:50 - 114:53
    You can use that. A
    dependent variable,
  • 114:53 - 114:55
    do you have anxiety symptoms?
  • 114:55 - 114:59
    Yeah, there's a couple
    that I could use.
  • 114:59 - 115:07
    One of them is the Beck
    anxiety inventory.
  • 115:07 - 115:11
    Then I think I
    found another one.
  • 115:11 - 115:15
    It's a brief symptom inventory,
  • 115:15 - 115:19
    which that one's like 53 items.
  • 115:19 - 115:23
    Then, I think it looks
    at anxiety and, like,
  • 115:23 - 115:30
    a handful of other I don't
    want to say disorders,
  • 115:30 - 115:33
    but, like, other types
    of mental things.
  • 115:33 - 115:34
    Illnesses?
  • 115:34 - 115:35
    Yeah.
  • 115:35 - 115:37
    At this point, I think it's up
  • 115:37 - 115:39
    to you what you want to use.
  • 115:39 - 115:40
    Okay.
  • 115:40 - 115:42
    I would look through
  • 115:42 - 115:43
    both of the Beck
    depression inventory
  • 115:43 - 115:46
    and the other anxiety
    scale and look to see
  • 115:46 - 115:50
    whether one has more questions
  • 115:50 - 115:53
    on it that reveals a
    variety of symptomology,
  • 115:53 - 115:55
    because you're looking at
    differences in symptomology.
  • 115:55 - 115:56
    Does it also look at physical
  • 115:56 - 115:59
    versus psychological symptoms?
  • 115:59 - 116:02
    Just use whichever one
    you think is best.
  • 116:02 - 116:04
    I think I looked at one with you
  • 116:04 - 116:07
    the Beck depression or Beck
    anxiety inventory, right?
  • 116:07 - 116:08
    Yeah.
  • 116:08 - 116:10
    I think I liked that one,
  • 116:10 - 116:11
    but as a researcher, these are
  • 116:11 - 116:12
    the questions that
    we have, right?
  • 116:12 - 116:16
    You just have to bite
    the bullet and decide.
  • 116:17 - 116:21
    I'm looking for the inventory.
  • 116:21 - 116:24
    Can you read me a few questions?
  • 116:24 - 116:26
    For which one?
  • 116:26 - 116:29
    The anxiety inventory.
  • 116:29 - 116:34
    The Beck one or the
    briefs one. The Beck one.
  • 116:34 - 116:37
    For the Beck anxiety one, it's,
  • 116:37 - 116:39
    like, a scale from 0-3,
  • 116:39 - 116:41
    and, like, a couple of them are
  • 116:41 - 116:43
    like numbness and
    tingling, feeling hot.
  • 116:43 - 116:47
    Yeah, I like this one. I
    have it on my computer.
  • 116:47 - 116:49
    Because I think it has
  • 116:49 - 116:55
    physical and psychological
    measures of anxiety.
  • 116:55 - 116:58
    I think this one would be
    good. This one doesn't seem
  • 116:58 - 117:00
    like too long to complete
    for your participants.
  • 117:00 - 117:01
    Okay.
  • 117:01 - 117:04
    You just need to compare
    this across the other one,
  • 117:04 - 117:06
    which is 48 questions.
  • 117:12 - 117:17
    Yeah. Because the other one
    is like a scale of 0-4,
  • 117:17 - 117:20
    and then it's like in
    the past seven days,
  • 117:20 - 117:23
    were you distressed by
    these various things.
  • 117:23 - 117:26
    Then, yeah, it's like 53 items.
  • 117:28 - 117:30
    It really is up to you.
  • 117:30 - 117:34
    I would look at the other one
    to see if they have, again,
  • 117:34 - 117:37
    psychological and physical
    symptoms of anxiety because I
  • 117:37 - 117:38
    think that's what you're
  • 117:38 - 117:40
    looking for
    differences in, right?
  • 117:41 - 117:45
    I would also include
    another dependent measure
  • 117:45 - 117:52
    maybe something
    positive, well being.
  • 117:52 - 117:54
    As a separate scale or?
  • 117:54 - 117:56
    Yeah, because if you're only
  • 117:56 - 117:57
    measuring personality
    and anxiety,
  • 117:57 - 117:58
    then they'll probably
    guess that you're
  • 117:58 - 118:00
    measuring personality
    and anxiety.
  • 118:00 - 118:01
    Okay.
  • 118:01 - 118:03
    Yeah. Maybe one more measure.
  • 118:03 - 118:07
    But it sounds like you've
    already found some good scales.
  • 118:07 - 118:10
    I think the problem now is
    deciding which one to use.
  • 118:10 - 118:14
    At this point, I feel
    like the Beck anxiety
  • 118:14 - 118:17
    is pretty widely
    and commonly used.
  • 118:17 - 118:19
    I haven't heard
    of the other one,
  • 118:19 - 118:20
    but I'm also not a
    clinical psychologist,
  • 118:20 - 118:24
    so it's up to you.
  • 118:24 - 118:25
    Okay.
  • 118:25 - 118:26
    Yeah.
  • 118:26 - 118:27
    All right. Thank you.
  • 118:27 - 118:29
    Yeah, of course. Let me
  • 118:29 - 118:30
    know if you have
    any more questions.
  • 118:30 - 118:31
    Okay.
  • 118:32 - 118:35
    All right, Hey, how
    can I help you?
  • 118:35 - 118:39
    Okay. I guess my
    real question is,
  • 118:39 - 118:41
    like, well, okay.
  • 118:41 - 118:48
    My independent variables
    are age and gender,
  • 118:48 - 118:52
    and then dependent is how
    they're treated at work and
  • 118:52 - 118:56
    I am just unsure of how to,
  • 118:56 - 118:58
    like, what I would use to
  • 118:58 - 119:02
    measure treatment
    at work, I guess.
  • 119:04 - 119:09
    Let's see. Based on the
    articles that you've read,
  • 119:09 - 119:10
    so you're going to need to
  • 119:10 - 119:12
    be more specific about
    treatment at work.
  • 119:12 - 119:15
    Are you talking about
    sexual harassment at work?
  • 119:16 - 119:19
    Yeah. In my introduction,
  • 119:19 - 119:26
    I made the distinction of
    harmful workplace experiences.
  • 119:26 - 119:32
    That included a lot
    of different things,
  • 119:32 - 119:34
    including, like,
    sexual harassment or
  • 119:34 - 119:39
    just harassment
    that's non sexual.
  • 119:39 - 119:43
    Okay. Here's a sexual
    harassment questionnaire.
  • 119:48 - 119:52
    Or maybe a toxic work
    environment questionnaire?
  • 119:52 - 119:54
    Yeah.
  • 119:56 - 119:58
    For your independent variables,
  • 119:58 - 119:59
    you're just basically
    going to ask,
  • 119:59 - 120:02
    what is your gender.
    How old are you?
  • 120:02 - 120:11
    Yeah.
  • 120:21 - 120:25
    This is a master's thesis.
  • 120:29 - 120:31
    You might need to
    look for that scale.
  • 120:31 - 120:34
    I think the key here is for you
  • 120:34 - 120:36
    to more clearly operationalize
  • 120:36 - 120:38
    what you mean treatment at work.
  • 120:38 - 120:40
    Do you mean sexual harassment?
  • 120:40 - 120:42
    If you want that
    to be a component,
  • 120:42 - 120:43
    then you might need to look for
  • 120:43 - 120:46
    a sexual harassment scale.
  • 120:47 - 120:49
    Let me try to find one.
  • 120:49 - 120:53
    I think this racialized
    sexual harassment scale,
  • 120:53 - 120:55
    which you might not want.
  • 120:55 - 120:59
    Psychological climate
    for sexual harassment.
  • 121:07 - 121:09
    I just want to see it all.
  • 121:09 - 121:13
    I think the sexual
    harassment is like
  • 121:13 - 121:19
    the angle of what I want to
    see within the age groups.
  • 121:19 - 121:23
    I think the treatment
    at work, I guess,
  • 121:23 - 121:25
    would just be have
  • 121:25 - 121:29
    you experience sexual
    harassment at work? Like that.
  • 121:29 - 121:32
    This is one climate.
  • 121:32 - 121:34
    It would be risky for me to file
  • 121:34 - 121:35
    a sexual harassment complaint.
  • 121:35 - 121:37
    Complaint would not
    be king seriously,
  • 121:37 - 121:39
    would not be thoroughly
    investigated, etc.
  • 121:39 - 121:42
    This is like the
    climate at work.
  • 121:43 - 121:46
    Let me look at your paper
  • 121:46 - 121:47
    because I feel like
    in your paper you
  • 121:47 - 121:53
    talked about some scales.
  • 121:56 - 121:59
    I still need to grade some.
  • 121:59 - 122:09
    Speed grader. I need to look at.
  • 122:19 - 122:21
    There are differences
    in how people
  • 122:21 - 122:23
    are treated in the
    workplace because of these.
  • 122:23 - 122:26
    What measure do they use?
  • 122:27 - 122:36
    Give me a second.
    Sorry, no, I find.
  • 122:36 - 122:39
    That's okay. That article.
  • 122:41 - 122:47
    It says, Hold it one second.
  • 122:47 - 122:56
    Sorry. Like within
    their method section?
  • 122:58 - 123:02
    I think they did
    a meta analysis.
  • 123:02 - 123:04
    You might need to look at
  • 123:04 - 123:06
    the actual articles
    that they cited.
  • 123:06 - 123:09
    But another one
    that actually has
  • 123:09 - 123:11
    dependent measures is this one
  • 123:11 - 123:12
    a confirmatory study
    of the relations
  • 123:12 - 123:14
    between workplace sexism,
  • 123:14 - 123:17
    sense of belonging, mental
    health, job satisfaction.
  • 123:17 - 123:19
    So those might be things
    that you're interested in.
  • 123:19 - 123:21
    Sexism, sense of belonging,
  • 123:21 - 123:24
    mental health, job satisfaction.
  • 123:27 - 123:28
    That one.
  • 123:28 - 123:52
    No sorry,
  • 123:52 - 123:56
    I'm reading to try
    and find like there.
  • 123:56 - 124:00
    It says sorry, go ahead.
  • 124:00 - 124:02
    I've received fewer
    opportunities for promotion.
  • 124:02 - 124:05
    I have less job stability.
  • 124:07 - 124:10
    Those are the skills
    that you can use.
  • 124:22 - 124:25
    You can even look
    at the schedule of
  • 124:25 - 124:28
    sexist events by
    Klanef and Landren.
  • 124:32 - 124:35
    You don't have to
    create your own skills.
  • 124:35 - 124:37
    Usually, this is why you
    read papers because you want
  • 124:37 - 124:41
    to see what kind of skills
    other people have used.
  • 124:41 - 124:43
    Let me see job satisfaction,
  • 124:43 - 124:47
    mental health, using
    depression anxiety scale.
  • 124:48 - 124:52
    Job satisfaction
    was measured using
  • 124:52 - 124:55
    the four item index of
    effective job satisfaction.
  • 124:55 - 124:57
    I find real enjoyment in my job.
  • 124:57 - 125:00
    I like my job better than
    the average person, etc.
  • 125:01 - 125:07
    Then, in my hypothetical
    experiment,
  • 125:07 - 125:11
    I would just use the
    job satisfaction,
  • 125:11 - 125:12
    a couple of questions
    from there,
  • 125:12 - 125:18
    and the sexism questions
    and just mix it up
  • 125:18 - 125:22
    so that the
    participants don't find
  • 125:22 - 125:23
    out what I'm trying to ask
  • 125:23 - 125:26
    or hopefully they
    don't find out.
  • 125:26 - 125:28
    Well, you're not going to mix
  • 125:28 - 125:30
    the job satisfaction
    with the sexism items.
  • 125:30 - 125:35
    You will have them like
    in a in a specific order.
  • 125:35 - 125:37
    Let me show you, like
    what that looks like.
  • 125:38 - 125:41
    Let me show you
    one of my studies.
  • 125:45 - 125:50
    This is what you'll
    use in 467468.
  • 125:52 - 125:56
    Oh, I don't think that
    one's the finish.
  • 125:56 - 126:02
    Oh, this one. It's 68
    participants. Skip two.
  • 126:10 - 126:14
    They either get
    geographic mobility
  • 126:14 - 126:17
    or they get diversity,
  • 126:17 - 126:21
    and then they get questions
    of individual mobility.
  • 126:22 - 126:26
    Then they get questions
    about group status.
  • 126:26 - 126:30
    Then they get questions about
    all these other things.
  • 126:30 - 126:33
    You can randomize
    the extent to which
  • 126:33 - 126:37
    these like how these
    variables appear.
  • 126:37 - 126:39
    But you want to keep all the job
  • 126:39 - 126:40
    satisfaction questions together.
  • 126:40 - 126:43
    You want to keep all the
    sexism questions together.
  • 126:45 - 126:47
    I didn't mean mix them together,
  • 126:47 - 126:52
    but just include other
    scales of different things.
  • 126:52 - 126:59
    You can. This is my
    manipulation check.
  • 126:59 - 127:01
    Please describe what
    the articles about.
  • 127:01 - 127:06
    What years the article I read
    today was about, whatever.
  • 127:08 - 127:10
    Does that make more sense?
  • 127:10 - 127:11
    You don't have to
    create your own.
  • 127:11 - 127:13
    I think that's the most
    stressful part for people.
  • 127:13 - 127:16
    You can just look through
    the articles that you
  • 127:16 - 127:19
    cited and see what kind
    of measures they used.
  • 127:19 - 127:20
    You don't have to use all of
  • 127:20 - 127:22
    the measures that this person,
  • 127:22 - 127:26
    whatever article we were
    looking at used, this one.
  • 127:26 - 127:28
    You can use some from here.
  • 127:28 - 127:29
    You can use some from
  • 127:29 - 127:33
    here if you want to look at
    sexual harassment climate.
  • 127:33 - 127:36
    Excuse me. Sorry.
  • 127:36 - 127:37
    Bless you.
  • 127:37 - 127:44
    Thank you. But I would maybe
    choose three or four total.
  • 127:44 - 127:46
    I think for yours,
  • 127:46 - 127:47
    yours is pretty straightforward.
  • 127:47 - 127:51
    I don't think you're going to
    need extra surveys to mask
  • 127:51 - 127:58
    your study you could just make
    it about job experiences,
  • 127:58 - 128:00
    and all of these are
    about job experiences.
  • 128:01 - 128:04
    Does that make
    sense? Yes, that's
  • 128:04 - 128:06
    much clearer now. Thank you.
  • 128:06 - 128:07
    Of course. If you want me
  • 128:07 - 128:09
    to look at a draft, let me know.
  • 128:09 - 128:12
    Or if you want to decide
    on your measures,
  • 128:12 - 128:13
    also let me know.
  • 128:13 - 128:15
    But at this point,
    it's mostly about
  • 128:15 - 128:17
    how you want to operationalize
  • 128:17 - 128:20
    it and what you want to measure.
  • 128:20 - 128:21
    Sounds good.
  • 128:21 - 128:24
    Cool.
  • 128:24 - 128:26
    Maybe I'll ask you
    on Wednesday to see
  • 128:26 - 128:30
    how your decisions going.
    Maybe three or four.
  • 128:30 - 128:33
    I will look into that today.
  • 128:33 - 128:35
    Sounds good. Well,
  • 128:35 - 128:36
    good luck. I will see
    you on Wednesday.
  • 128:36 - 128:38
    See you on Wednesday.
Title:
5.3 - More on Experiments
Video Language:
English
Duration:
02:08:40

English subtitles

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