How is an ex post facto design more advantageous than a correlational design?

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Quizplus · Accepted Answer

An ex post facto design is more advantageous than a correlational design because it allows for a greater degree of experimental control. In an ex post facto design, the independent variable has already occurred, so the researcher has control over selecting and grouping participants based on that variable. In contrast, correlational designs cannot manipulate the independent variable, and therefore have less experimental control.

How Is an Ex Post Facto Design More Advantageous Than