In a Study Comparing Two Nonequivalent Groups, a Selection-History Confound

question 40

Multiple Choice

In a study comparing two nonequivalent groups, a selection-history confound occurs when

• A) some event intervenes between pretest and posttest and affects just one of the groups.
• B) some event intervenes between pretest and posttest and affects both selected groups equally.
• C) selection influences one of the groups and history influences the other.
• D) some historical event causes a failure of the random assignment procedure.

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