A problem with using random assignment to produce equivalence between an experimental and a control group is that:
A)it doesn't work well without matching.
B)it increases the amount of extraneous variability.
C)it reduces the internal validity of the experiment.
D)it can yield nonequivalent groups on occasion.

Question

A problem with using random assignment to produce equivalence between an experimental and a control group is that:
A)it doesn't work well without matching. 
B)it increases the amount of extraneous variability.
C)it reduces the internal validity of the experiment.
D)it can yield nonequivalent groups on occasion.

Quizplus · Accepted Answer

Random assignment is generally a robust method for achieving group equivalence, but it is not foolproof. On occasion, due to chance, it can result in groups that are not equivalent on some measures, which is why replication and larger sample sizes are often recommended to mitigate this risk.

A Problem with Using Random Assignment to Produce Equivalence Between