Juhani T. Linnainmaa
University of Southern California
Marshall School of Business
701 Exposition Blvd, Ste. 231
Los Angeles, CA 90089-1422
NBER Program Affiliations:
NBER Affiliation: Research Associate
NBER Working Papers and Publications
|December 2016||Asset Managers: Institutional Performance and Smart Betas|
with Joseph Gerakos, Adair Morse: w22982
Using a dataset of $17 trillion of assets under management, we document that actively-managed institutional accounts outperformed strategy benchmarks by 86 (42) basis points gross (net) during 2000–2012. In return, asset managers collected $162 billion in fees per year for managing 29% of worldwide capital. Estimates from a Sharpe (1992) model imply that their outperformance comes from factor exposures ("smart beta"). If institutions had instead implemented mean-variance portfolios of institutional mutual funds, they would not have earned higher Sharpe ratios. Recent growth of the ETF market implies that asset managers are losing advantages held during our sample period.
|The History of the Cross Section of Stock Returns|
with Michael R. Roberts: w22894
Using data spanning the 20th century, we show that most accounting-based return anomalies are spurious. When examined out-of-sample by moving either backward or forward in time, anomalies' average returns decrease, and volatilities and correlations with other anomalies increase. The data-snooping problem is so severe that even the true asset pricing model is expected to be rejected when tested using in-sample data. Our results suggest that asset pricing models should be tested using out-of-sample data or, when not feasible, by whether a model is able to explain half of the in-sample alpha.
Published: Juhani T Linnainmaa & Michael R Roberts, 2018. "The History of the Cross-Section of Stock Returns," The Review of Financial Studies, vol 31(7), pages 2606-2649.
|December 2014||Common Factors in Return Seasonalities|
with Matti Keloharju, Peter Nyberg: w20815
A strategy that selects stocks based on their historical same-calendar-month returns earns an average return of 13% per year. We document similar return seasonalities in anomalies, commodities, international stock market indices, and at the daily frequency. The seasonalities overwhelm unconditional differences in expected returns. The correlations between different seasonality strategies are modest, suggesting that they emanate from different common factors. Our results suggest that seasonalities are not a distinct class of anomalies that requires an explanation of its own---rather, they are intertwined with other return anomalies through shared common factors. A theory that is able to explain the risks behind any common factor is thus likely able to explain a part of the seasonalities.
|November 2014||Retail Financial Advice: Does One Size Fit All?|
with Stephen Foerster, Brian T. Melzer, Alessandro Previtero: w20712
Using unique data on Canadian households, we assess the impact of financial advisors on their clients' portfolios. We find that advisors induce their clients to take more risk, thereby raising expected returns. On the other hand, we find limited evidence of customization: advisors direct clients into similar portfolios independent of their clients' risk preferences and stage in the life cycle. An advisor's own portfolio is a good predictor of the client's portfolio even after controlling for the client's characteristics. This one-size-fits-all advice does not come cheap. The average client pays more than 2.7% each year in fees and thus gives up all of the equity premium gained through increased risk-taking.
Published: STEPHEN FOERSTER & JUHANI T. LINNAINMAA & BRIAN T. MELZER & ALESSANDRO PREVITERO, 2017. "Retail Financial Advice: Does One Size Fit All?," The Journal of Finance, vol 72(4), pages 1441-1482.