We develop a model of portfolio choice to nest the views of Keynes - who advocates concentration in a few familiar assets - and Markowitz - who advocates diversification across assets. We rely on the concepts of ambiguity and ambiguity aversion to formalize the idea of an investor’s...

We investigate how information processing frictions contribute to household suboptimal saving and investment behavior. We find that 60% of open accounts in college 529 savings plans are invested suboptimally due to high expenses and tax inefficiency. Such investments yield an expected loss of 9%...

Using the "firm" quotes obtained from the tick-by-tick EBS (electronic broking system that is a major trading platform for foreign exchanges) data, it is found that risk-free arbitrage opportunities--free lunch--do occur in the foreign exchange markets, but it typically last only a few seconds....

We empirically examine the order flows spillovers between Nasdaq and the Forex markets in 2008 and 2009. With emphasis on a role of high-frequency traders (HFTs) who aggregate information between the two markets as well as within each market, our results show that HFTs in Nasdaq trade...

Investors hold a substantially larger proportion of their wealth portfolios in domestic assets than standard portfolio theory would suggest, a phenomenon called "equity home bias." In the absence of this bias, investors would optimally diversify domestic output risk using foreign equities....

Berkshire Hathaway has realized a Sharpe ratio of 0.76, higher than any other stock or mutual fund with a history of more than 30 years, and Berkshire has a significant alpha to traditional risk factors. However, we find that the alpha becomes insignificant when controlling for exposures to...

The paper examines the performance of US no-load equity mutual funds. Fund performance is derived using stochastic frontier analysis for a flexible functional form. This analysis allows us to derive parametric estimates of efficiency scores for each fund in our sample for the first time in the...

This article analyzes the manifold situations in which the efficient-market hypothesis (EMH) has influenced—or has failed to influence—federal securities regulation and state corporate law, and the prospective roles for the EMH in these contexts. In federal securities regulation, the EMH has...

This paper focuses on analyzing functional relationships among performance measures, centered on the adjusted differential risk premium between the asset and the benchmark and on Sharpe-1994 ratio. First, we develop a risk normalization procedure for variance and Aumann–Serrano riskiness which...

Three concepts: stochastic discount factors, multi-beta pricing and mean-variance efficiency, are at the core of modern empirical asset pricing. This chapter reviews these paradigms and the relations among them, concentrating on conditional asset-pricing models where lagged variables serve as...