In a between-subjects design, individual differences (participant variables) are a problem because they can ____.
A) cause diffusion and attrition
B) increase variability of the scores
C) preclude the use of statistical analyses
D) produce fatigue effects

Question

Quizplus · Accepted Answer

In a between-subjects design, individual differences can increase the variability of the scores, which can make it harder to detect significant differences between groups. This is why researchers often try to control for participant variables by matching participants on relevant characteristics or using random assignment. Diffusion and attrition are issues that can affect both between-subjects and within-subjects designs, while fatigue effects are more of a concern in within-subjects designs where participants may become tired or bored from repeated testing. Precluding the use of statistical analyses is not a direct result of participant variables, but rather a failure to design the study with appropriate measures or a lack of statistical power.

In a Between-Subjects Design, Individual Differences (Participant Variables) Are a Problem