Current time:0:00Total duration:2:32

0 energy points

# Constructing a scatter plot

Sal shows how to construct a scatter plot. Created by Sal Khan.

Video transcript

Aubrey wanted to see if there's
a connection between the time a given exam takes place and
the average score of this exam. She collected data about
exams from the previous year. Plot the data in a scatter plot. And let's see, they give
us a couple of rows here. This is the class. Then they give us
the period of the day that the class happened. And then they give us the
average score on an exam. And we have to be a little
careful with the study-- maybe there's some
correlation depending on what subject is taught
during what period. But let's just use her data, at
least, just based on her data, see if-- well, definitely
do what they're asking us, plot a scatter plot, and then
see if there is any connection. So let's see. On the horizontal
axis, we have Period. And on this investigation,
this exploration she's doing, she's trying to see, well,
does the period of the day somehow drive average score? So that's why Period is
on the horizontal axis. And the thing that's driving
is on the horizontal, the thing that's being driven
is on the vertical. So let's plot each
of these points. Period 1, average score
93-- right over there. Period 6, 87. Oh, that's not the
right place, and then we can move it if we want--
87, right over there. Period 2, 70. Period 4, 62-- right over there. Period 4 and 86, that's
right over there. Period 1, 73. Period 3, average
score of 73 as well. Period 1, 80,
average score of 80. And then Period 3,
average score of 96. So there we go. And it doesn't really
seem like there's any obvious trend over here. So let's make sure
that we got this right. And we did.