Functional measurement methodology applied to a subjective probability model of cognitive functioning

Used functional measurement procedures to test R. S. Wyer and L. Goldberg's subjective probability model of cognitive organization. 54 undergraduates estimated the likelihood that a hypothetical person had an attribute (PB) on the basis of information that directly affected their beliefs that persons in general have a particular gene (Pa) and that persons who do not have this gene possess the attribute (Pb/a and Pb/a'). Pa interacted significantly with both Pb/a and Pb/a'; each of these interactions was concentrated in the bilinear component, supporting the assumption that each pair of beliefs has multiplicative effects upon Pb. A small but significant interaction of Pb/a and Pb/a' was also detected, contrary to implications of the model. Although the model provided a good quantitative description of the relations among the beliefs involved without the necessity of introducing ad hoc curve-fitting parameters, small but significant discrepancies from prediction were detected. These discrepancies suggested that Pa and Pb/a were weighted appropriately, but that Pb/a' should receive a weight inversely proportional to its magnitude. In sum, results support the general formulation proposed. (PsycINFO Database Record (c) 2006 APA, all rights reserved).