Dr. Evil's "Rate My Professor" rating keeps getting higher, even though he tries to keep it as low as possible (he was down to 0.2!) He decides he must be getting nicer in his old age and to be meaner than ever to his statistics students this year! The change in Dr. Evil's ratings are most likely due to
A) statistical significance.
B) a median split.
C) an illusory correlation.
D) regression to the mean.
E) None of the above

Question

Quizplus · Accepted Answer

The change in Dr. Evil's ratings is most likely due to regression to the mean, which is a statistical phenomenon that occurs when extreme measurements tend to be closer to the average on subsequent measurements. Given that his rating was extremely low (0.2), any random variation in how students rate him would likely result in higher ratings, simply because there's more room for the ratings to increase than to decrease.

Dr Evil's "Rate My Professor" Rating Keeps Getting Higher, Even