This paper examines the conditions required to guarantee positive prices in the CAPM. Positive prices imply an upper bound on the equity premium. This upper bound depends on the degree of diversity of firms’ fundamentals, and it is independent of investors’ preferences. In economies with realistically diverse assets the only positive-price CAPM equilibrium theoretically possible is a degenerate...

Robust portfolio optimization has been developed to resolve the high sensitivity to inputs of the Markowitz mean-variance model. Although much effort has been put into forming robust portfolios, there have not been many attempts to analyze the characteristics of portfolios formed from robust optimization. We investigate the behavior of robust portfolios by analytically describing how robustness...

This paper considers two methods for pricing assets and examines the relations between them. The +rst method is based on the principle of no-arbitrage, which asserts that introduction of the new asset should not create an arbitrage in a market that was before arbitrage free. This condition is satis+ed by prices for the new asset between speci+c lower and upper limits, determined as the values o...

This paper presents a potential solution to the home bias puzzle based on a new open economy macroeconomics model. In response to technology shocks, sticky prices generate a negative correlation between labor income and the profits of domestic firms, leading to home bias in equity holdings. In contrast, under flexible prices, labor income and the profits of the domestic firms are positively cor...

We consider portfolio allocation in which the underlying investment instruments are hedge funds. We consider a family of utility functions involving the probability of outperforming a benchmark and expected regret relative to another benchmark. Non-normal return vectors with prescribed marginal distributions and correlation structure are modeled and simulated using the normal-to-anything method...

This paper provides a dynamic rational expectations equilibrium model in which investors have heterogeneous information and investment opportunities. Informed investors privately receive advance information about future earnings that is unrelated to current earnings. In response to good advance information, stock prices increase and informed investors act as trend chasers, increasing their inve...

——————————————————————————————————— We study optimal portfolio choice in a two-country model where assets represent claims on future consumption and facilitate trade in markets with imperfect credit. Assuming that foreign assets trade at a cost, agents hold relatively more domestic assets. Consequently, agents have larger claims to domestic over foreign consumption. Moreover, foreign assets tur...

Using a calibrated OLG model with several sources of uncertainty we find that the impact of ageing and of reform of social security upon the demand for housing and the level of owner occupation is substantial. The overall structure of household asset holdings in particular the split between real and financial assets is sensitive to demographics and to the generosity of state run, pay-as-yougo p...

We investigate the implications of technological innovation and non-diversifiable risk on entrepreneurial entry and optimal portfolio choice. In a real options model where two risk-averse individuals strategically decide on technology adoption, we show that the impact of non-diversifiable risk on the option timing decision is ambiguous and depends on the frequency of technological change. Compa...