00:01
We are given the sample of data points listed at the top of this document, and using that data, we want to answer the following six questions, a through s.
00:09
We'll proceed together one by one as follows.
00:12
First, in part a, we want to produce a scatter plot of our data points.
00:15
I've already included this scatter plot right below part a on the left, where the points x, y are marked with black x's or crosses.
00:23
Next, directly to the right, we want to compute for part b.
00:26
This sums relevant to this data as well as the pearson correlation coefficient r.
00:30
I've already included the values of the sums, since they are found simply by taking the exact formulas for those sums, so sum x with some of the x values and so on.
00:39
Correlation coefficient r is given by the following formula, which takes as input, our sample size n, and the sum we just calculated.
00:47
Plugging those in, we get r equals 0 .084.
00:52
Next, in part c, we want to find the line of best fit for this data.
00:58
To do so, we have to identify the following parameters first.
01:01
First, our x mean and y mean, x bar and y bar, which are simply the sum of our x and y values divided by n.
01:08
We can use these now to find the slope b and intercept a of the line of best fit...