To test whether extracurricular activity is a good predictor of college success, a college administrator recorded whether students participated in extracurricular activities during high school and their subsequent college freshman GPA.
Extracurricular Activity ______________________ College Freshman GPA
Yes .....................................................................3.52
Yes .....................................................................3.33
Yes .....................................................................3.91
Yes .....................................................................3.70
No.......................................................................2.96
No.......................................................................3.84
No.......................................................................3.42
No.......................................................................2.76
No.......................................................................3.88
No.......................................................................2.80
(a) Compute a point-biserial correlation coefficient.
(b) Using a two-tailed test at a .05 level of significance, state the decision to retain or reject the null hypothesis.