THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A professor of statistics is interested in studying the relationship between the number of hours graduate students spent studying for his comprehensive final exam and the exam score.The results of the regression analysis of hours studied on exam scores are presented below.
-The covariance between the two variables x and y:
A)has the same sign as the coefficient of correlation.
B)is always greater than zero.
C)is always smaller than zero.
D)is computed by dividing by the number of (x,y)pairs.

Question

THE NEXT QUESTIONS ARE BASED ON THE FOLLOWING INFORMATION:
A professor of statistics is interested in studying the relationship between the number of hours graduate students spent studying for his comprehensive final exam and the exam score.The results of the regression analysis of hours studied on exam scores are presented below. 
-The covariance between the two variables x and y:
A)has the same sign as the coefficient of correlation. 
B)is always greater than zero. 
C)is always smaller than zero. 
D)is computed by dividing by the number of (x,y)pairs.

Quizplus · Accepted Answer

The covariance between two variables has the same sign as the coefficient of correlation. So, if the correlation is positive, the covariance will be positive as well, and if the correlation is negative, the covariance will be negative.