Raising a classification threshold shrinks the population as a nested subset.

Evidence

Clearly, whether the threshold should be high or low depends on the theoretical, substantive, normative, causal, and empirical considerations. The choice of a threshold will usually influence causal inference and statistical analyses. One can think of increasing thresholds as populations that are subsets of each other. The population with a high threshold is a subset of the population with a lower threshold. — Gary Goertz, Social Science Concepts and Measurement, 1004

Categorization

• XREF: Same nested-subset logic recurs in the ethnocracy example and in welfare-state service counts.