Effect on r of Exchanging x and y Values Examine the computation formula for r, the sample correlation coefficient [formulas (1) and (2) of this section].

(a) In the formula for r, if we exchange the symbols x and y, do we get a different result or do we get the same (equivalent) result? Explain.

(b) If we have a set of x and y data values and we exchange corresponding x and y values to get a new data set, should the sample correlation coefficient be the same for both sets of data? Explain.

(c) Compute the sample correlation coefficient r for each of the following data sets and show that r is the same for both.

x 1 3 4 y 2 1 6 x 2 1 6 y 1 3 4 AppendixLO1