In which of the following selection procedures is regression towards mean least likely to occur?

false
false
Students with the highest math ability are selected.
false
Workers with the lowest morale are selected.
false
Patients with the most severe symptoms are selected.
true
Leaders with average leardership ability are selected.
Regression towards the mean occurs when the sample or subjects are chosen on the basis of extreme scores.
Assume a test has a mean of 200 and a standard deviation of 50. Suppose a student took the test and got 350 and wanted to take a retest.
If the test-retest correlation were 0.80, what would be the predicted score for the retest?

320
0.01
350 is (350 - 200)/50 = 3 standard deviations above the mean. Therefore it has a standard score equivalent of 3.
Since the test-retest correlation is 0.80, the predicted standard score would be (0.80)(3)=2.4, which means
the predicted score would 2.4 standard deviation above the mean. Therefore, the predicted score would be 200+(2.4)(50)=320.