In the standard CAPM with a riskless asset we give a simple proof of existence of equilibria without assuming concavity of the investor's utility functions. Moreover, we give a uniqueness result using assumptions on the risk aversion of investors.

Markowitz and Sharpe won the Nobel Prize in Economics more than a decade ago for the development of Mean-Variance analysis and the Capital Asset Pricing Model (CAPM). In the year2002, Kahneman won the Nobel Prize in Economics for the development of Prospect Theory....

Under the assumption of normally distributed returns, we analyzewhether the Cumulative Prospect Theory of Tversky and Kahneman (1992) is consistent with the Capital Asset Pricing Model. We find that in every financial market equilibrium the Security Market Line Theorem holds....

In the standard CAPM with a riskless asset we give a sufficient condition for uniqueness. This condition is a joint restriction on the agents' endowments and their preferences which is compatible with non-increasing absolute risk aversion and which is in particularsatisfied with constant...

Markowitz and Sharpe won the Nobel Prize in Economics more than a decade ago for the development of Mean-Variance analysis and the Capital Asset Pricing Model (CAPM). In the year 2002, Kahneman won the Nobel Prize in Economics for the development of Prospect Theory. Can these two apparently...

Under the assumption of normally distributed returns, we analyzewhether the Cumulative Prospect Theory of Tversky and Kahneman (1992)is consistent with the Capital Asset Pricing Model. We find that in everyfinancial market equilibrium the Security Market Line Theorem holds.However, under the...

The paper examines a dynamic model of a financial market with endogenous asset prices determined by short run equilibrium of supply and demand. Assets pay dividends that are partially consumed and partially reinvested. The traders use fixed-mix investment strategies (portfolio rules),...

We demonstrate that in a CAPM economy Walras Law and the Tobin Separation Property characterize market demand in finite sets of prices. Consequently, for any number n there exist CAPM economies which have at least n equilibria and hence have n different beta pricing fomulas. It is shown that the...

Under the assumption of normally distributed returns, we analyze whether the Cumulative Prospect Theory of Tversky and Kahneman (1992) is consistent with the Capital Asset Pricing Model. We find that in every financial market equilibrium the Security Market Line Theorem holds. However, under the...

We consider economies with additively separable utility functions and give conditions for the two-agents case under which the existence of sunspot equilibria is equivalent to the occurrence of the transfer paradox. This equivalence enables us to show that sunspots cannot matter if the initial...