Arandom sample of factory workers is selected. Each worker is given an IQ test and also a factual “Current Events” test. The mean IQ for the group is 110 with an estimated standard deviation of 12.85. The mean score on the “Current Events” test is 50 with an estimated standard deviation of 15.

a. Assume a significant correlation of .95 and predict the IQ of a worker whose “Current Events” score is only 20.

b. Assume a significant correlation of .25 and again predict the IQ of a worker whose

“Current Events” score is only 20.

c. Why is the IQ prediction in part b higher than the prediction in part a? (Hint: Note the sizes of the two correlations used and recall the meaning of regression.)