We present a model of technological adaptation in response to a change in climate conditions. The main feature of the model is that new technologies are not just risky, but also ambiguous. Pessimistic agents are thus averse to adopting a new technology. Learning is induced by optimists, who are...

In this paper we suggest a behavioral approach to decision making under ambiguity based on available information. A decision situation is characterized by a set of actions, a set of outcomes, and data consisting of action-outcome pairs. Decision-makers express preferences over actions and data...

In this paper, we consider a decision maker who tries to learn the distribution of outcomes from previously observed cases. For each observed database of cases the decision maker predicts a set of priors expressing his beliefs about the underlying probability distribution. We impose a version of...

We model decision making under ambiguity based on available data. Decision makers express preferences over actions and data sets. We derive an α-max–min representation of preferences, in which beliefs combine objective characteristics of the data (number and frequency of observations) with...

I consider an economy populated by case-based decision makers. Consumption can be transferred between the periods by means of a riskless storage technology or a risky asset with i.i.d. dividend payments. I analyze the dynamics of asset holdings and asset prices and identify the influence of the...

In this paper, we consider a decision-maker who tries to learn the distribution of outcomes from previously observed cases. For each observed sequence of cases, the decision-maker entertains a set of priors expressing his hypotheses about the underlying probability distribution. The set of...

This paper explores the problem of a social planner willing to improve the welfare of individuals who are unable to compare all available alternatives. The optimal decision trades off the individuals' desire for flexibility versus their aversion towards ambiguous choice situations. We introduce...