Two experiments show that violations of expected utility due to ambiguity, found in general decision experiments, also affect belief aggregation. Hence we use modern ambiguity theories to analyze belief aggregation, thus obtaining more refined and empirically more valid results than traditional...

This article develops a new approach to study the impact on beliefs and decisions of uncertain probability forecasts by advisors. The core concept of that approach, which builds on the revealed-preference approach favored by economists, is the one of revealed beliefs - the precise probability...

Testing whether risk professionals (here insurers) behave differently under risk and ambiguity when they cover catastrophic risks (floods and earthquakes) and non-catastrophic risks (fires), this paper reports the results of the first field experiment in the United States designed to distinguish...

In this paper, we build on the emerging literature on group decision-making to study the so-called ‘group shift’ effect, i.e., groups are less risk-averse than individuals. Our study complements past research in two ways. First, we study the group shift effect under two sources of...

In an experimental setting, we applied a dual strategy to better understand the effect of pictures of eyes on human behavior. First, we investigated whether the effect of eyes was limited to interaction tasks in which the subjects' decisions influenced the outcomes of other subjects. We expanded...

This paper introduces the Prince incentive system for measuring preferences. Prince is a variation of the random incentive system that enhances isolation and makes incentive compatibility more transparent to subjects. It allows for the precise and direct elicitation of indifference values as...

We propose simple behavioral definitions of comparative uncertainty aversion for a single agent towards different sources of uncertainty. Our definitions allow for the comparison of utility curvature towards different sources if the agent's choices satisfy subjective expected utility towards...

Despite widespread exposure to substantial medical expenditure risk in low-income populations, health insurance enrollment is typically low. This is puzzling from the perspective of expected utility theory. To help explain it, this paper introduces a decomposition of the stated willingness to...

Temporary incentives are offered in anticipation of persistent effects, but these are seldom estimated. We use a nationwide randomized experiment in the Philippines to estimate effects three years after the withdrawal of two incentives for health insurance. A premium subsidy had a persistent...

Many important decisions are made without precise information about the probabilities of the outcomes. In such situations, individual ambiguity attitudes influence decision making. The present study identifies affective states as a transient cause of ambiguity attitudes. We conducted two...