Selecting cases with extreme values on causes biases tests against necessity

Evidence

Skocpol may have selected England and Japan precisely because peasant revolts were totally absent even though the cases resembled social revolutions in certain important respects. This kind of selection procedure in which a case is chosen because it has a very low value on a causal variable but a reasonably high value on the outcome variable is almost certain to violate causal necessity. — Gary Goertz, Social Science Concepts, 1752

Categorization

• SEED: Article angle: case-selection strategies that look rigorous can systematically pre-determine which causal claims survive empirical testing.