糖心TV

Capacity restrictions in human judgment

Making accurate judgments such as choosing a job candidate presumes an adequate weighting of more and less important aspects, say the candidate’s skills. People may find out the importance of different cues by testing rules specifying how the cues relate to the criterion. In this talk, I will present evidence from three studies suggesting that this ability to test rules is restricted by working memory capacity. In a large individual difference study, we first investigated how working memory and episodic memory affect judgment accuracy. The ability to solve rule-based tasks was predicted by working memory, whereas episodic memory predicted judgment accuracy in the exemplar-based task. Second, increasing working memory load reduced the prevalence of rule-based strategies and ultimately benefitted judgment accuracy in a task that could not be solved by rules. In a final step, we incorporated the assumption that a capacity limit restricts rule-based learning into a learning model and tested it against two alternative psychological mechanisms: a decay in learning speed and attentional learning. A capacity-restricted learning model best described and predicted the learning curve of the majority of participants. Taken together, these studies suggest that learning to accurately weigh the importance of different aspects is limited by working memory capacity.