Title

Markowitz Meets Talmud: A Combination of Sophisticated and Naive Diversification Strategies

Publication Type

Journal Article

Publication Date

2011

Abstract

The modern portfolio theory pioneered by Markowitz (1952) is widely used in practice and extensively taught to MBAs. However, the estimated Markowitz portfolio rule and most of its extensions not only underperform the naive 1/N rule (that invests equally across N assets) in simulations, but also lose money on a risk-adjusted basis in many real data sets. In this paper, we propose an optimal combination of the naive 1/N rule with one of the four sophisticated strategies—the Markowitz rule, the Jorion (1986) rule, the MacKinlay and Pástor (2000) rule, and the Kan and Zhou (2007) rule—as a way to improve performance. We find that the combined rules not only have a significant impact in improving the sophisticated strategies, but also outperform the 1/N rule in most scenarios. Since the combinations are theory-based, our study may be interpreted as reaffirming the usefulness of the Markowitz theory in practice.

Keywords

Portfolio choice, Mean-variance analysis, Parameter uncertainty

Discipline

Finance and Financial Management | Portfolio and Security Analysis

Research Areas

Finance

Publication

Journal of Financial Economics

Volume

99

Issue

1

First Page

204

Last Page

215

ISSN

0304-405X

Identifier

10.1016/j.jfineco.2010.08.013

Publisher

Elsevier