00:01
We are given the set of data points listed at the top of this whiteboard, xy, and we want to use these data points to answer the following questions a through f.
00:10
Starting off with part a on the left, we want to produce a scatter plot of these data points.
00:14
I've already included the scatter plot, as you can see, where the data points x, y, are demarcated by the black crosses or x's.
00:22
Next to the right in part b, we want to compute the sums relevant to this data as well as the pearson correlation coefficient r.
00:29
The sums are given by following the formula exactly, so some x is the sum of the x values, some y is some of the individual y values, and so on.
00:37
To compute r, we use the following formula, which takes as input our sample size n, and the sum is just computed.
00:43
This gives r equals 0 .9126.
00:46
Next below in part c, we want to find the equation of the line of best fit, which requires finding these parameters first.
00:52
Our sample mean x bar and our sample mean y bar are given by the sum of our x values about it by n, 6 .25, and then some of our y values over n 32 .8.
01:04
We can find the parameters for our best fit line, b and a as follows.
01:08
The slope b is given by the equation here, which takes us input in the sample size and the sums we found above...