Parameter space partitioning (PSP) is a versatile tool for model analysis that detects the qualitatively distinctive data patterns a model can generate, and partitions a model's parameter space into regions corresponding to these patterns. In this paper, we propose a PSP fit measure that summarizes the outcome of a PSP analysis into a single number, which can be used for model selection. In contrast to traditional model selection methods, PSP-based model selection focuses on qualitative data. We demonstrate PSP-based model selection by use of application examples in the area of category learning. A large-scale model recovery study reveals excellent recovery properties, suggesting that PSP fit is useful for model selection.
Keywords: Categorization; Model selection; Parameter space partitioning; Qualitative model fit.