Hindsight Bias Through Knowledge Updating: A Conceptual Replication of Groß et al. (2023)

Hindsight bias is the phenomenon that after learning facts about previouslyjudged objects people tend to recall their previous judgments of the objects as closer tothe facts than they actually were. Groß, Kreis, Blank, and Pachur (2023) found thathindsight bias emerged not only when people learned actual values for previouslyjudged objects, but also when they learned the values of other objects in the samedomain. Moreover, hindsight bias co-occurred with improved estimates for new objects.These findings challenge the traditional view that hindsight bias reflects a cognitiveerror and instead suggest that it results from adaptive knowledge updating. Groß et al.(2023) obtained their findings in the domain of country populations, a domain wherepeople tend to be unfamiliar with the content and the numerical range (up to severalmillion); this lack of familiarity may affect the link between knowledge updating andhindsight bias. In a high-powered conceptual replication (N = 300), we tested whetherthe findings generalize to the sugar content of food items—a domain where people aremore familiar with both content and numerical range (up to 50 grams). Participantsprovided original judgments for items, learned numerical information, then recalledtheir original judgments, and lastly provided judgments for a new set of items. Ourresults replicate the key results of Groß et al. (2023), showing a close link betweenhindsight bias and knowledge updating in a more familiar domain. We discussimplications for theories of hindsight bias and propose directions for future research.