CeDEx Brown Bag Seminar - Marcelo Woo

Title: Contagious ignorance: theory and experiment on the interdependence of information avoidance 

Abstract: People often choose not to know: they avoid information that could help them make better decisions. This paper asks whether such information avoidance can be interdependent within groups. Inspired by Bénabou (2013), our theoretical model predicts that when avoidance is socially harmful, individuals' willingness to remain ignorant may exhibit strategic complementarities (making ignorance contagious), strategic substitutabilities (making it self-limiting), or unconditional behavior. We test these predictions in a lab experiment where remaining ignorant about the state worsens the payoffs of all group members. Consistent with contagious ignorance, participants are, on average, more likely to avoid information when they expect others to do the same. Elicited anticipatory utilities suggest that the contagion is mediated by a deterioration of the expected utility of learning bad news. Beyond the average effect, individuals differ: some act as strategic complements, others as substitutes, and some unconditionally acquire or avoid information. Simulations show that group composition affects the distribution of equilibrium avoidance monotonically and nonlinearly. Our findings nuance insights from the literature on individual decision-making: incentivizing one individual or subgroup to acquire information may alter others' incentives, suggesting that policies should account for potential crowding-in or crowding-out effects.

Marcelo is on the academic job market in 2025-26.