Membership in ‘high test score’ is sharply asymmetric, saturating only in the top percentiles.

Evidence

While I do not include the semantic mapping figure it is clear from this description that the semantic transformation for “high test score” is very asymmetric and nonlinear to the underlying percentiles. For example, 0.0 membership starts already at about the 60th percentile and 1.0 membership starts at the 93rd percentile, while the “middle” is the 80th percentile. — Gary Goertz, Social Science Concepts and Measurement, 717

Categorization

• DEEPTHINKING: The median of the underlying scale (50th percentile) sits well below the crossover point — the ‘average’ person is by definition not a member, which quietly rewrites what ordinary means.