Understanding time investment while solving problems is central to metacognitive research. By the Diminishing Criterion Model (DCM), time regulation is guided by two stopping rules: a confidence criterion that drops as time is invested in each problem and the maximum time to be invested. This combination generates curved confidence–time associations. We compared the belief that intelligence is malleable, a growth mindset, to the belief that intelligence is fixed, and to neutral control groups. We hypothesized that a growth mindset leads people (...) to selectively invest time in problems carrying the hope of improvement. This extra time makes the curved DCM pattern curvier. In two experiments, participants primed with growth, fixed, or control mindsets solved analogies (Experiment 1) and compound remote associates (Experiment 2). As expected, in both experiments a growth mindset exhibited a curvier confidence–time pattern, while the fixed mindset and control groups replicated previous confidence–time associations. Most additional time was invested in problems with intermediate difficulty levels, suggesting strategic time allocation. The study offers useful measures for delving into factors that affect thinking time allocation. (shrink)

Initial Judgment of Solvability (iJOS) is a metacognitive judgment that reflects solvers’ first impression as to whether a problem is solvable. We hypothesized that iJOS is inferred by combining prior expectations about the entire task with heuristic cues derived from each problem’s elements. In two experiments participants first provided quick iJOSs for all problems, then attempted to solve them. We manipulated expectations by changing the proportion of solvable problems conveyed to participants, 33%, 50%, or 66%, while the true proportion was (...) the 50% for all. In Experiment 1 we used the non-verbal Raven’s matrices and examined nameability as the element-based heuristic cue. Unsolvable matrices were generated by switching locations of elements in original Raven’s matrices. In Experiment 2 we used the verbal Compound Remote Associate (CRA) problems and examined word’s frequency in the language as the element-based heuristic cue. Unsolvable CRAs were random word triads from the same word pool. The results were consistent in suggesting that quick iJOS integrates prior expectations and experience-based heuristic cues. Notably, iJOS was predictive for the subsequent solving attempt only for Raven’s matrices. (shrink)