__________ is likely to be a threat to internal validity whenever subjects are assigned to experimental conditions on the basis of their low or high scores on the pretest.
A) Testing
B) Differential attrition
C) Instrumentation
D) Statistical regression

Question

Quizplus · Accepted Answer

Statistical regression is a threat to internal validity when subjects are selected based on extreme scores, as their scores tend to move towards the mean on subsequent tests.

__________ Is Likely to Be a Threat to Internal Validity