Majority views and confidence information promote informed decisions

Abstract In a world where verifying facts is challenging and individual opinions are pervasive, how do people leverage the “wisdom of crowds”? We presented decision-makers with true or false statements and evaluated how they use varying levels of social information, from others’ views to confidence levels and higher-order beliefs, to form their judgments. Our results show that social information combining majority opinion and confidence data is particularly effective in fostering factual knowledge, benefiting easy questions and less knowledgeable individuals without significantly harming performance on difficult questions or by more knowledgeable participants. However, individuals revise their beliefs infrequently and often rely on majority opinion as the decision heuristic, even when richer information is available. Confidence data, though informative, remains underutilized. These findings highlight both the promise and limits of crowd-based decision-making, and point to opportunities for improving collective judgment by designing information environments that support more effective use of available cues.