Models of dependence and independence: A two-dimensional architecture of dual processing

This theoretical note proposes a two-dimensional cognitive architecture for dual-process theories of reasoning and decision making. Evans (2007b, 2008a, 2009) distinguishes between two types of dual-processing models: parallel-competitive, in which both types of processes operate in parallel, and default-interventionist, in which heuristic processes precede the analytic processes. I suggest that this temporal dimension should be enhanced with a functional distinction between interactionist architecture, in which either type of process influences the content and valence of the other, and independent architecture, in which they do not. Override architecture is a special case of the latter, which postulates statistical interaction, but no interaction of valence and content. I show that this added dimensional distinction casts doubt on two assumptions of statistical modelling that Evans makes: independence and linearity. However, Evans' (2007b) point, that statistical modelling is underspecified vis-a-vis the verbal theory, is given further support. The functional dimension is crucial to interpreting the statistical model, as well as to theoretical understanding of the cognitive architecture and its educational applications.