Categories and continua: a review of taxometric research.

The taxometric procedures developed by Paul Meehl and his colleagues have been used in a large body of research seeking to distinguish between categorical and continuous models of latent variables. In this article the authors survey taxometric studies of psychopathological, personality, and other variables and draw conclusions about the taxonicity of latent variables in these domains. In addition, the authors review research on the validation and refinement of taxometric methods and make proposals for improving the application of taxometric research. The authors consider questions that remain about the conceptual status of taxometrics and raise new ones. They show that taxometric methodology has made an accelerating number of contributions to psychological research, has resolved several longstanding controversies, and has challenged some entrenched theoretical assumptions in differential psychology. Moreover, they contend that the research possibilities that it affords have yet to be fully exploited.