Mental models in predictive reasoning with perceptual and semantic base rates: A developmental perspective

In this study, pre-schoolers and a comparison sample of with graders and hi gh school students were presented with prediction tasks that varied by cont ent of the base rate information (perceptual vs semantic) either presented alone (simple task) or accompanied by individuating data (complex task). Ba se rate choices, confidence scores, and explanations of the choices were re gistered. It is assumed that the presence of content effects in the process ing of the base rates is in favour of a mental model account. Results indic ated that pre-schoolers are able to build one-dimensional models with perce ptual base rates in simple tasks. Fifth graders and high school students ar e able to build one-dimensional models with both types of content in simple tasks, as well as two-dimensional models in complex tasks. There is a loca l facilitation effect of semantic contents for fifth graders that disappear s for high-school students. Consistency between subjects' choices, confiden ce scores and rationales depends on the subjects' grade, the number of sour ces involved, and the base rate content. Developmental trends are discussed in the light of previous research within formal, heuristic, and mental mod el approaches.