Robert Stambaugh is the Miller Anderson & Sherrerd Professor of Finance at the Wharton School of the University of Pennsylvania. He is a Fellow and former President of the American Finance Association, a Fellow of the Financial Management Association, and a Research Associate of the National Bureau of Economic Research. Professor Stambaugh has been the editor of the Journal of Finance, an editor of the Review of Financial Studies, an associate editor of those journals as well as the Journal of Financial Economics, and a member of the first editorial committee of the Annual Review of Financial Economics. He has published articles on topics including return predictability, asset pricing tests, portfolio choice, parameter uncertainty, liquidity risk, volatility, performance evaluation, investor sentiment, and active-versus-passive investing. His research awards include a Smith-Breeden first prize for an article in the Journal of Finance as well as a Fama-DFA first prize and three second prizes for articles in the Journal of Financial Economics. Before joining Wharton in 1988, he was Professor of Finance at the University of Chicago, where he received his PhD in 1981. Professor Stambaugh visited Harvard University as a Marvin Bower Fellow in 1997-98.
Abstract: We present a model of investing based on environmental, social, and governance (ESG) criteria. In equilibrium, green assets have negative alphas, whereas brown assets have positive alphas. The ESG investment industry is at its largest, and the alphas of ESG-motivated investors are at their lowest, when there is large dispersion in investors' ESG preferences. When this dispersion shrinks, so does the ESG industry, even if all investors' ESG preferences are strong. Greener assets are more exposed to an ESG risk factor, which captures shifts in customers' tastes for green products or investors' tastes for green holdings. Under plausible conditions, the latter tastes produce positive social impact.
Abstract: We construct size and value factors in China. The size factor excludes the smallest 30% of firms, which are companies valued significantly as potential shells in reverse mergers that circumvent tight IPO constraints. The value factor is based on the earnings-price ratio, which subsumes the book-to-market ratio in capturing all Chinese value effects. Our three-factor model strongly dominates a model formed by just replicating the Fama and French (1993) procedure in China. Unlike that model, which leaves a 17% annual alpha on the earnings-price factor, our model explains most reported Chinese anomalies, including profitability and volatility anomalies.
Abstract: We study tradeoffs among active mutual funds' characteristics. In both our equilibrium model and the data, funds with larger size, lower expense ratio, and higher turnover hold more-liquid portfolios. Portfolio liquidity, a concept introduced here, depends not only on the liquidity of the portfolio's holdings but also on the portfolio's diversification. We also confirm other model-predicted tradeoffs: Larger funds are cheaper. Larger and cheaper funds are less active, based on our new measure of activeness. Better-diversified funds hold less-liquid stocks; they are also larger, cheaper, and trade more. These tradeoffs provide novel evidence of diseconomies of scale in active management.
Abstract: The Critical Finance Review commissioned Li, Novy-Marx, and Velikov (2017) and Pontiff and Singla (2019) to replicate the results in Pastor and Stambaugh (2003). Both studies successfully replicate our market-wide liquidity measure and find similar estimates of the liquidity risk premium. In the sample period after our study, the liquidity risk premium estimates are even larger, and the liquidity measure displays sharp drops during the 2008 financial crisis. We respond to both replication studies and offer some related thoughts, such as when to use our traded versus non-traded liquidity factors and how to improve the precision of liquidity beta estimates.
Abstract: Greater skill of active investment managers can mean less fee revenue in equilibrium. Although more-skilled managers receive more revenue than less-skilled managers, greater skill for active managers overall can imply less revenue for their industry. Greater skill allows managers to identify mispriced securities more accurately and thereby make better portfolio choices. Greater skill also means, however, that active management corrects prices better and thus reduces managers’ return opportunities. The latter eﬀect can outweigh managers’ better portfolio choices in a general equilibrium. Investors then rationally allocate less to active funds and more to index funds if active management is more skilled.
Abstract: A pre-specified set of nine prominent U.S. equity return anomalies produce significant alphas in Canada, France, Germany, Japan, and the U.K. All of the anomalies are consistently significant across these five countries, whose developed stock markets afford the most extensive data. The anomalies remain significant even in a test that assumes their true alphas equal zero in the U.S. Consistent with the view that anomalies reflect mispricing, idiosyncratic volatility exhibits a strong negative relation to return among stocks that the anomalies collectively identify as overpriced, similar to results in the U.S.
Abstract: A four-factor model with two “mispricing” factors, in addition to market and size factors, accommodates a large set of anomalies better than notable four- and five-factor alternative models. Moreover, our size factor reveals a small-firm premium nearly twice usual estimates. The mispricing factors aggregate information across 11 prominent anomalies by averaging rankings within two clusters exhibiting the greatest co-movement in long-short returns. Investor sentiment predicts the mispricing factors, especially their short legs, consistent with a mispricing interpretation and the asymmetry in ease of buying versus shorting. Replacing book-to-market with a single composite mispricing factor produces a better-performing three-factor model.
Abstract: Lower skill of the active management industry can imply greater fee revenue, value added, and investor performance. Such outcomes arise in a competitive equilibrium in which portfolio choices of active managers partially echo those of noise traders and also contain manager-specific noise. Both sources of noise reduce managers' skill to identify mispriced securities and thereby produce alpha. However, lower skill also means a given amount of active management corrects prices less and thus competes away less alpha. The latter effect can outweigh managers' poorer portfolio choices, so that investors rationally allocate more to active management when its skill is lower.
This course studies the concepts and evidence relevant to the management of investment portfolios. Topics include diversification, asset allocation, portfolio optimization, factor models, the relation between risk and return, trading, passive (e.g., index-fund) and active (e.g., hedge-fund, long-short) strategies, mutual funds, performance evaluation, long-horizon investing and simulation. The course deals very little with individual security valuation and discretionary investing (i.e., "equity research" or "stock picking").
FNCE205001 ( Syllabus )
FNCE205002 ( Syllabus )
This course studies the concepts and evidence relevant to the management of investment portfolios. Topics include diversification, asset allocation, portfolio optimization, factor models, the relation between risk and return, trading, passive (e.g., index-fund) and active (e.g., hedge-fund, long-short) strategies, mutual funds, perfermance evaluation, long-horizon investing and simulation. The course deals very little with individual security valuation and discretionary investing (i.e., "equity research" or "stock picking").
FNCE720001 ( Syllabus )
For hedge funds, poor performance, closures and large investor withdrawals are raising questions about their future. But don’t expect hedge funds to disappear anytime soon.Knowledge @ Wharton - 2015/11/6