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Understanding picture and bar graphs

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    - What do you see here
    are two different ways
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    of looking at the same information.
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    So, for example, if I were to ask you,
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    and you could look at either
    this graph on the left
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    or this graph on the right,
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    what type of squirrel do they find
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    the most of at the park?
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    What would your answer be?
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    Well, the way that you
    would try to answer that,
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    let's say you were to look
    at this graph on the left,
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    which is a picture graph.
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    You might say, "Where
    does that name come from?"
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    Well, it's using pictures.
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    And these pictures usually
    are some type of symbol,
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    or in this case, an actual
    picture of a squirrel
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    that shows you the things
    that we're counting.
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    Now, before you even just
    count the picture graph,
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    the pictures in the picture graph,
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    it's important to look at the key here
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    and make sure that you know
    what each squirrel picture.
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    They almost look like cats here.
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    What each of these squirrel
    pictures represent here,
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    each squirrel represents one squirrel,
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    so it's pretty straightforward,
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    but it could have been two
    squirrels or three squirrels,
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    or four and a half squirrels,
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    which would've been very strange,
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    but it's one squirrel.
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    So if you wanted to know
    which one has the most,
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    and I guess it would've been the most,
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    regardless of what this key said,
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    even if it was two squirrels,
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    you can see just by looking at it
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    that you see the most gray squirrels here.
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    There's the most number of
    these little squirrel pictures.
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    We can actually know exactly
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    how many gray squirrels there are.
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    There are 1, 2, 3, 4, 5, 6, 7, 8
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    of these pictures.
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    Each of them represent one squirrel,
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    so there are eight gray squirrels.
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    Now, we could have also used
    this graph at the right,
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    and this is called a bar graph.
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    Why?
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    Because you have these
    bars to show how much
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    of each type of squirrel you have,
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    and so we can make sure we can confirm
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    that the gray squirrels right over here.
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    This is also showing that you have eight,
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    and with a bar graph, this
    one has it nicely numbered,
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    where we see that each
    line increases by one.
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    We go from 1, 2, 3, 4, 5, 6, 7, 8, 9.
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    Sometimes it's not labeled as neatly,
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    and sometimes each of these vertical lines
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    might represent two or three or four.
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    So it's always good to make sure,
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    but this one's pretty straightforward.
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    So we can see here there
    are eight gray squirrels.
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    Now these can also be useful
    for making comparisons.
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    So, for example, if I were to say
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    how many more fox squirrels were found
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    at the park than red squirrels?
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    Well, you could look at either of these.
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    Let's start with the bar graph here.
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    We could see the red squirrels.
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    There's five.
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    The fox squirrels has six,
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    so there's one more.
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    There's one more fox
    squirrel than red squirrel.
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    You can see that here.
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    The red squirrel fives, fox squirrel.
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    The red (chuckles)
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    There are five red squirrels,
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    and then you can see there
    are six fox squirrels.
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    You could think of this one
    as the one that goes above
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    and beyond the number of
    red squirrels we have.
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    So both picture and bar graphs
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    can be good ways of thinking
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    of the quantities.
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    You see, they're good
    for making comparisons.
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    They're good for figuring
    out just how many
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    of something you see or
    what's the difference,
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    or even the total of different categories.
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    Here, it's the squirrel types.
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    Now, it's also important to realize
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    what this is not going to tell you.
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    This isn't necessarily going
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    to even tell you the
    color of the squirrels.
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    You might say, "Oh
    look, this picture graph
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    looks like this squirrel.
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    Is this gray/blue color?"
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    No, you can't just assume
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    how it's drawn is actually what it is.
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    It's just a symbol.
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    For example, I'm guessing
    that a red squirrel
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    is more reddish, and a gray squirrel,
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    and maybe a gray squirrel is more grayish.
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    But this doesn't tell
    you what they look like.
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    This doesn't tell you how hard
    it was to collect the data.
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    You don't know how long it took.
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    You don't know anything else
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    about the squirrel's behavior,
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    what they might eat, et cetera.
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    You just know how many of each type
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    of squirrel was found at the park.
Title:
Understanding picture and bar graphs
Description:

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Video Language:
English
Team:
Khan Academy
Duration:
03:45

English subtitles

Incomplete

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