Divergent Productions of Metaphors: Combining Many-Facet Rasch Measurement and Cognitive Psychology in the Assessment of Creativity

This article presents a new method for the assessment of creativity in tasks such as "The camel is ... of the desert." More specifically, the study uses Tourangeau and Sternberg's (1981) domain interaction model to produce an objective system for scoring metaphors produced by raters and the many-facet Rasch measurement to model the rating scale structure of the scoring points, item difficulty, and rater severity analysis, thus making it possible to have equated latent scores for subjects, regardless of rater severity. This study also investigates 4 aspects of the method: reliability, correlation between quality and quantity, criterion validity, and correlation with fluid intelligence. The database analyzed in this study consists of 12,418 responses to 9 items that were given by 975 persons. Two to 10 raters scored the quality and flexibility of each metaphor on a 4-point scale. Raters were counterbalanced in a judge-linking network to permit the equating of different "test forms" implied in combinations of raters. The reliability of subjects' latent quality scores was .88, and the correlation between quality and quantity was low (r = -.14), thus showing the desired separation between the 2 parameters established for the task scores. The latent score on the test was significantly associated with the profession that requires idea production (r = .19), and the latent scores for the correlation between creativity and fluid intelligence were high, beta = .51, even after controlling for crystalized intelligence (r = .47). Mechanisms of fluid intelligence, executive function, and creativity are discussed.