Fifty students have taken a 100-item true-false test. For each student, let X be the number of questions answered correctly and Y be the number not answered correctly. We would expect r to be
A) +1.00
B) zero
C) -1.00
D) between zero and -1.00

Question

Quizplus · Accepted Answer

Since X and Y are perfectly negatively correlated (Y = 100 - X), the correlation coefficient r would be -1.00.

Fifty Students Have Taken a 100-Item True-False Test