_______________ refers to the assigning of test units to treatment groups in such as way that the groups differ on the dependent variable before the presentation of the treatments.
A) The main testing effect
B) Test unit mortality
C) Selection bias
D) The instrumentation effect

Question

Quizplus · Accepted Answer

If the test units already differ in terms of the dependent variable before the treatment is given,then selection bias has occurred.

_______________ Refers to the Assigning of Test Units to Treatment