In a study of the factors that affect success in economics,data were collected for 8 business students.Scores on a calculus placement test are given with economics final exam scores.The data are below. It can be shown that for these data: 140.75. Calculate the sample correlation coefficient.
A)0.15
B)0.11
C)0.39
D)-0.39
E)-0.11

Question

In a study of the factors that affect success in economics,data were collected for 8 business students.Scores on a calculus placement test are given with economics final exam scores.The data are below.  It can be shown that for these data:  140.75. Calculate the sample correlation coefficient.
A)0.15 
B)0.11 
C)0.39 
D)-0.39 
E)-0.11

Quizplus · Accepted Answer

Using the formula for the sample correlation coefficient, we get:

r = [(8 x 4205) - (355 x 450)] / [(8 x 14975 - (355)^2) x (8 x 315 - (450)^2)]^(1/2)
r = 0.39

Therefore, the sample correlation coefficient is 0.39, which corresponds to choice C.

In a Study of the Factors That Affect Success in Economics,data