The Three Levels of Generalizability

The theory of generalizability (Cronbach, et al. , 1972) and Loevinger's (1957) analysis of construct validity are examined in an effort to extend the concept of generalizability and to reformulate some aspects of Loevinger's analysis. Three levels of generalizability emerge from this examination: Generalizability from scale score to location on an unspecified personality dimension (reliability), from scale score to location on a vertically defined personality dimension (trait validity), and from scale score to location on a vertically and horizontally defined personality dimension (nomological validity).