title: Predicting the size of individual and group differences on speeded cognitive tasks.
abstract: An a priori test of the difference engine model (Myerson, Hale, Zheng, Jenkins, & Widaman, 2003) was conducted using a large, diverse sample of individuals who performed three speeded verbal tasks and three speeded visuospatial tasks. Results demonstrated that, as predicted by the model, the group standard deviation (SD) on any task was proportional to the amount of processing required by that task. Both individual performances as well as those of fast and slow subgroups could be accurately predicted by the model using no free parameters, just an individual or subgroup's mean z-score and the values of theoretical constructs estimated from fits to the group SDs. Taken together, these results are consistent with post hoc analyses reported by Myerson et al. and provide even stronger supporting evidence. In particular, the ability to make quantitative predictions without using any free parameters provides the clearest demonstration to date of the power of an analytic approach on the basis of the difference engine.
authors.affiliation: Department of Psychology, Grand Valley State University, Allendale, Michigan 49401, USA. chenj@gvsu.edu
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Sandra
authors.initials: S
authors.lastname: Hale
authors.forename: Joel
authors.initials: J
authors.lastname: Myerson
mesh_terms: D000293:Adolescent; D000328:Adult; D003071:Cognition; D003657:Decision Making; D006126:Group Processes; D006801:Humans; D007600:Judgment; D008824:Michigan; D011930:Reaction Time