WEBVTT

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- [Instructor] We're told that
administrators at a school

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are considering a policy change.

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They survey a group of
students, staff members,

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and parents about
whether or not they agree

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with the new policy.

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The following mosaic plot
summarizes their results.

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Which of the following
statements can we justify

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from the mosaic plot?

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So pause this video and try to
figure this out on your own.

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Pick which of these
statements can be justified

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and there could be more than
one based on this mosaic plot.

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All right, now let's work
through this together.

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So before I even look at the choices,

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let me see if I can interpret this.

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So this mosaic plot,

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what it does above and
beyond a segmented bar chart,

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is it gives us the width
that shows us how many,

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for example, students
versus staff versus parents

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were sampled or surveyed.

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And it looks like more than half

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of the people surveyed were students.

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And then staff and parents seem similar.

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In terms of who is
agreeing with the policy,

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so that's that light blue color.

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It seems like students are
not very likely to agree

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with the policy.

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It looks like staff is very
likely to agree with the policy,

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that the bulk of staff
is agreeing with it.

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And parents are kind of on both sides.

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So let's see which of these
statements are consistent

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with what we just looked at.

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Parents were the least likely
to agree with the new policy.

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No, that's not true.

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The least likely to
agree with the new policy

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that's students, right over here.

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They were definitely the least likely.

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The lowest percentage of students

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are agreeing with the policy.

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So I don't like that choice.

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More than half of the total
responses came from students.

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And that does look like the case.

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'Cause if you view this entire
width as the total responses,

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it looks like the student
width right over here,

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that is more than half of it.

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It looks like it's about
50 something percent

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or even 60 percent.

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So I like this choice right over here.

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And then last but not least,

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there were more total "No"
responses from students

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than from staff and parents combined.

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So let's look at the no
responses from students.

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No, that's that darker blue color.

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The no responses for students
is this area right over here.

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And then the nos, so I can,
maybe I'll shade all of that in,

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and then the no responses from staff

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and parents combined, that
is this area right over here.

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And it does look like indeed
the total no responses

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from students, this area is much larger

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than this area right over here.

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So I like this choice as well.