Search and Learning

People often do not know ahead of time what the consequences of their decisions will be or how likely those consequences are to occur. One way of making informed decisions is to explore the options and learn more about the possible outcomes and their likelihoods. We investigate this search process—how people learn about choice options, how they allocate their attention during search, and how learning impacts people’s decisions strategies and attitudes towards risk. We have also recently begun exploring deliberate ignorance, the decision to remain ignorant of what the future might hold and not search for information at all.

How Learning Influences Risk Preferences

People can learn about the potential consequences of their options and the associated probabilities in two ways: by reading about them or by personally experiencing them. We have observed a “description–experience gap,” a phenomenon by which rare events are given too much weight in decisions from description and too little weight in decisions from experience. We have found the description–experience gap to be robust and to generalize across domains including investment decisions, intertemporal choice, and adolescent risk taking.

How Learning Influences Strategy Use

We also investigate how the way people experience options during learning influences the type of knowledge they use to make subsequent decisions. We have found that when options are presented one by one, people tend to make decisions based on their memories of specific experiences; when options are presented in pairs, people tend to abstract a rule across experiences. This result suggests that learning materials could be designed in a way that encourages people to use a particular decision.

Attention Allocation During Search

Through lab experiments that track eye movements and the amount of time spent looking at different attributes, we examine the relationship between attention during search and the decisions made afterwards. Is it possible to predict a person’s decision based on the eye movements recorded during search?

Deliberate Ignorance

A more recent research avenue within our research group focuses on the decision to forgo search. Under some conditions, people choose to remain ignorant; for example, up to 55% of those who get tested for HIV do not return to pick up their results. We call the conscious choice not to seek or use information “deliberate ignorance.” What motivates individuals to do without information and what are the cognitive strategies underlying their choice?

References

• Appelhoff, S., Hertwig, R., & Spitzer, B. (2022). Control over sampling boosts numerical evidence processing in human decisions from experience. Cerebral Cortex. bhac062.
• Ciranka, S., Linde-Domingo, J., Padezhki, I., Wicharz, C., Wu, CM., & Spitzer, B. (2022). Asymmetric learning facilitates human inference of transitive relations. Nature Human Behaviour, 6, 555–564.
• Hertwig, R., & Erev, I. (2009). The description–experience gap in risky choice. Trends in Cognitive Sciences, 13, 517–523.
• Hertwig, R., & Engel, C. (2016). Homo ignorans: Deliberately choosing not to know. Perspectives on Psychological Science, 11, 359–372. 
• Pachur, T., Schulte-Mecklenbeck, M., Murphy, R. O., & Hertwig, R. (2018). Prospect theory reflects selective allocation of attention. Journal of Experimental Psychology: General, 147, 147–169.
• Trippas, D., & Pachur, T. (2019). Nothing compares: Unraveling learning task effects in judgment and categorization. Journal of Experimental Psychology: Learning, Memory, and Cognition, 45, 2239–2266.
• Wulff, D. U., Mergenthaler-Canseco, M., & Hertwig, R. (2018). A meta-analytic review of two modes of learning and the description–experience gap. Psychological Bulletin, 144, 140–176.