Question

(c) Compute the sample correlation coefficient r for each of the following data sets and show that r is the same for both. (Use 3 decimal places.) (i) x 6 1 9 y 4 2 5

(ii)x 4 2 5 y6 1 9

Answer 1

i.

	X	Y	X*Y	X2	Y2
	6	4	24	36	16
	1	2	2	1	4
	9	5	45	81	25
Sum =	16	11	71	118	45

ii.

	X	Y	X*Y	X2	Y2
	4	6	24	16	36
	2	1	2	4	1
	5	9	45	25	81
Sum =	11	16	71	45	118

Hence we see that interchanging x and y do not change the value of r.