Correlation vs Causation
Also called: correlation does not imply causation, causal inference
Correlation measures whether two variables move together; causation claims one produces the other. Two variables can correlate because one causes the other, because a third causes both, because the causation runs backwards, or by pure coincidence in a large enough search. Establishing causation needs an experiment or a credible identification strategy, which is why the phrase is a warning rather than a technique.
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