Desmond thinks his new tutoring methods are highly effective compared to commercially available methods.He selects the worst students in his statistics class and tries his new tutoring strategy.Which statement describes a threat to the validity of his hypothesis even if the students do very well after the tutoring sessions?
A) Instrumentation errors will skew the results.
B) Regression to the mean is likely to occur.
C) Confirmation bias is likely to occur.
D) The testing sequence is a confounding factor.

Question

Quizplus · Accepted Answer

Regression to the mean is likely to occur when studying extreme cases, such as the worst students in a class. These students may naturally improve even without the new tutoring methods, simply because they were starting from a very low point. Therefore, if they do well after the tutoring sessions, it may not necessarily be due to the effectiveness of Desmond's methods, but rather a natural tendency for improvement. This threatens the validity of his hypothesis that his methods are highly effective compared to commercially available methods. The other answer choices are either not relevant to the scenario or not significant sources of threats to validity in this case.

Desmond Thinks His New Tutoring Methods Are Highly Effective Compared