. . . and the Cross-Section of Expected Returns
Hundreds of papers and hundreds of factors attempt to explain the cross-section of expected returns. Given this extensive data mining, it does not make any economic or statistical sense to use the usual significance criteria for a newly discovered factor, e.g., a t-ratio greater than 2.0. However, what hurdle should be used for current research? Our paper introduces a multiple testing framework and provides a time series of historical significance cutoffs from the first empirical tests in 1967 to today. Our new method allows for correlation among the tests as well as missing data. We also project forward 20 years assuming the rate of factor production remains similar to the experience of the last few years. The estimation of our model suggests that a newly discovered factor needs to clear a much higher hurdle, with a t-ratio greater than 3.0. Echoing a recent disturbing conclusion in the medical literature, we argue that most claimed research findings in financial economics are likely false.
We appreciate the comments of Viral Acharya, Jawad Addoum, Tobias Adrian, Andrew Ang, Ravi Bansal, Mehmet Beceren, Itzhak Ben-David, Bernard Black, Jules van Binsbergen, Oliver Boguth, Tim Bollerslev, Alon Brav, Ian Dew-Becker, Robert Dittmar, Jennifer Conrad, Michael Cooper, Andres Donangelo, Wayne Ferson, Simon Gervais, Bing Han, John Hand, Andrew Karolyi, Abby Yeon Kyeong Kim, Lars-Alexander Kuehn, Sophia Li, Harry Markowitz, Kyle Matoba, David McLean, Marcelo Ochoa, Peter Park, Lubos Pastor, Andrew Patton, Lasse Heje Pedersen, Tapio Pekkala, Jeff Pontiff, Ryan Pratt, Alexandru Rosoiu, Tim Simin, Avanidhar Subrahmanyam, Ivo Welch, Basil Williams, Yuhang Xing, Josef Zechner and Xiaofei Zhao as well as seminar participants at the 2014 New Frontiers in Finance Conference at Vanderbilt University, the 2014 Inquire Europe-UK meeting in Vienna, the 2014 WFA meetings, and seminars at Duke University, University of Utah, and Penn State university. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.
Campbell R. Harvey & Yan Liu & Heqing Zhu, 2016. "… and the Cross-Section of Expected Returns," Review of Financial Studies, vol 29(1), pages 5-68.