eLife assessment
This behavioral modeling study investigates how humans make decisions on the difficulty of perceptual categorization tasks. The study finds that such judgments are best described by an evidence-accumulation model that includes a dynamic comparison of difficulty-related evidence, which terminates when the difference in evidence between two tasks reaches a predetermined bound – a valuable finding for research in perceptual decision-making. The paper provides compelling behavioral evidence for the proposed model through: 1) quantitative model selection/validation procedures, and 2) qualitative analyses of the relation between the optimal model of the task and the human data (and the proposed model).