Why, in general, are quasi-experiments not threatened by the directionality problem?

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Why, in general, are quasi-experiments not threatened by the directionality problem?



Answer: Like "real" experiments, most quasi-experiments are not open to reversed-causation explanations because (a) the subject variable was caused a long time ago and causation can't go backwards in time, (b) it's very hard for a variable to be more stable than its causes, and (c) most subject variables are random and permanent.

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