This paper introduces a novel approach to integrals with respect to capacities. Any random variable is decomposed as a combination of indicators. A pre-speci ed set of collections of events indicates which decompositions are allowed and which are not. Each allowable decomposition has a value determined by the capacity. The decomposition-integral of a random variable is de ned as the highest of ...

This paper provides a theoretical framework for pricing assets in a multiperiod economy with heterogeneous beliefs. The stock price dynamics follow a binomial lattice structure. Agents are allowed to differ in their beliefs of the probability and asset return in each state of nature. By constructing a consensus belief, we examine the impact of heterogeneous beliefs on market equilibrium. Static...

Recently Kajii and Ui [17] proposed to characterize interim efficient allocations in an exchange economy under asymmetric information when uncertainty is represented by multiple posteriors. When agents have Bewley’s incomplete preferences, Kajii and Ui [17] proposed a necessary and sufficient condition on the set of posteriors. However, when agents have Gilboa–Schmeidler’s MaxMin expected utili...

This paper analyzes the effects of information leakage on trading behavior and market efficiency. It shows that a trader who receives a leaked signal prior to a public announcement can exploit this private information twice. First, when he receives his signal, and second, at the time of the public announcement. The latter effect occurs because he can best infer the extent to which his informati...

Several papers have documented a regime switch in US monetary policy from ‘passive’ and destabilizing in the pre-1979 period to ‘active’ and stabilizing afterwards. These studies typically work with DSGE models with rational expectations. This paper relaxes the assumption of rational expectations and allows for learning instead. Economic agents form expectations from simple models and update th...

This paper analyzes the equilibrium play of individuals that are randomly matched to play a contest where the dominant action changes over time. Under myopic decision making, players adopt imitation strategies similar to those observed in evolutionary models with sampling from past play in the population. If the players are patient, equilibrium strategies display elements of experimentation in ...

This paper presents a Heterogeneous Agent Model of a financial market with chartist and fundamentalist traders that exhibit bounded rationality and short-term thinking to explain the effect of under and overreaction to news. The existence of the Market Maker’s finite price adjustment speed and the presence of risk aversion lead to the fact that prices do not adjust instantaneously to new inform...

This note considers Tobin’s average Q in a framework where firms finance investment by equities and debt. The determination of its long-run equilibrium value Qo is based on positing equality of the loan rate and, adjusted for a risk premium, the return on equities. Qo can thus be characterized as a ratio of two rates representing the somewhat modified interest costs and profits of the firms. Th...

We study the efficiency of categorization of other agents as a way of simplifying the decision problem that agents face when involved in a large game. We assume that, when an agent categorizes (partitions) her opponents, she can only observe the average strategy in each category. A strategy profile is a Conjectural Categorical Equilibrium (CCE) with respect to a given categorization profile if ...

Interacting agents in finance represent a behavioral, agent-based approach in which financial markets are viewed as complex adaptive systems consisting of many boundedly rational agents interacting through simple heterogeneous investment strategies, constantly adapting their behavior in response to new information, strategy performance and through social interactions. An interacting agent syste...