We analyze the effect of geographic proximity on individual investors' portfolio choice. Using a unique data set which covers the common stockholdings of private households at regional banks in Germany, we document strong and consistent overinvestment in geographically close companies. Our...

We study optimal selling strategies of a seller who is poorly informed about the buyer’s value for the object. When the maxmin seller only knows that the mean of the distribution of the buyer’s valuations belongs to some interval then nature can keep him to payoff zero no matter how much...

In this paper we provide an overview of decision frameworks aimed at crafting an energy technology Research & Development portfolio, based on the results of three large expert elicitation studies and a large scale energy-economic model. We introduce importance sampling as a technique for...

We study in an experiment whether humans prefer to depend on decisions of other humans (social uncertainty) or states of nature (environmental uncertainty). In the social uncertainty treatments subjects depend only on past decisions of other humans. This is the first experiment that studies...

Most models of ambiguity aversion satisfy Anscombe-Aumann's Monotonicity axiom. This paper proposes a test of Monotonicity, the Allais Horse Race. It is an adaptation of the Allais paradox to a setting with both subjective and objective uncertainty. Viewed as a thought experiment, the Allais...

Prospect theory (PT) is the dominant descriptive theory of decision making under risk today. For the modeling of choices, PT relies on a psychologically founded separation of risk attitudes into attitudes towards outcomes, captured in a value function; and attitudes towards probabilities,...

Prior research suggests that those who rely on intuition rather than effortful reasoning when making decisions are less averse to risk and ambiguity. The evidence is largely correlational, however, leaving open the question of the direction of causality. In this paper, we present experimental...

This paper focuses on information acquisition and individual decision making in ambiguous situations and presents a novel experimental design which may help to tackle open questions from a fresh perspective. Instead of giving subjects the choice between risky and ambiguous Ellsberg urns, we let...

We offer a theory of polarization as an optimal response to ambiguity. Suppose individual A's beliefs first-order stochastically dominate individual B's. They observe a common signal. They exhibit polarization if A's posterior dominates her prior and B's prior dominates her posterior. Given...

This paper experimentally investigates individual information acquisition and decisions in ambiguous situations in which the degree of ambiguity can endogenously and individually be decreased by the subjects. In particular, I analyze how risk aversion, ambiguity attitude and personality traits...