We prove that under very weak conditions optimal financial products have to be co-monotone with the inverted state price density. Optimality is meant in the sense of the maximization of an arbitrary preference model, e.g. Expected Utility Theory or Prospect Theory. The proof is based on methods...

We study how the framework of classical game theory changes when the preferences of the players are described by Prospect Theory instead of Expected Utility Theory. Specifically, we study the influence of framing effect and probability weighting on the existence and specific structure of Nash...

Prospect Theory is a widely accepted descriptive framework to model decisions under risk. However, it is limited to situations with finitely many outcomes. Moreover, it is discontinuous, i.e., small changes in a lottery can produce large differences in its utility, contrary to experiments. In...

We suggest a simple asset market model in which we analyze competitive and strategic behavior simultaneously. If two-fund separation is found to hold across periods for competitive behavior, it also holds for strategic behavior. In this case the relative prices of the assets do not depend on...

According to the traditional view held in finance returns of assets are determined by complete rationality of decision makers. Rational decisions are defined by a set of axioms that are universal and do not leave room for cultural differences. In this article we show that cultural differences do...

This paper studies an application of a Darwinian theory of portfolioselection to stocks listed in the Dow Jones Industrial Average (DJIA).We analyze numerically the long-run outcome of the competition offix-mix portfolio rules in a stock market with actual DJIA dividends.In the model seemingly...

There is an extensive literature claiming that it is often difficultto make use of arbitrage opportunities in financial markets. Thispaper provides a new reason why existing arbitrage opportunitiesmight not be seized. We consider a world with short-lived securities,no short-selling constraints...

Experimental stock markets are used to add some more evidence that Blacks (1976) leverage effect in financial markets does not necessarily stem from the financial leverage of the firm. We surprisingly find a large number of markets in which the leverage effect is observed although the underlying...

We consider a simple CAPM with heterogenous expectations on assets mean returns while keeping the assumption of homogenous expectations on the covariance of returns. Our first result derives the security market line as an aggregation result without using the two-fund-separation property. In...

The prospect theory of Kahneman and Tversky (1979) and the cumulative prospect theory of Tversky and Kahneman (1992) are descriptive models for decision making that summarize several violations of the expected utility theory. This paper gives a survey of applications of prospect theory to the...