Open-Ended Category-Based Induction: The Influence of Associative Strength and Structured Knowledge Representations

Accounts of category-based inductive reasoning can be distinguished by the emphasis they place on associative retrieval processes versus structural knowledge representation. Using an open-ended category-based induction task with a secondary task manipulation, we explored whether the relative importance of these two processes in determining the reasoning output depends upon the availability of mental resources. Regressing indices of strength of association and measures of structured relation against reasoners’ inferences showed that people’s inductions generated under cognitive load were more strongly predicted by associative strength between base and conclusion category. In contrast, inferences made under no load were best predicted by the measure of the existence of structural relations between base and conclusion category. This suggests that people make use of associative processes and recruit structured knowledge to make inductive inferences, and that the relative importance of these two forms of reasoning is determined by the availability of mental resources.