Understanding Peer Effects in Financial Decisions: Evidence from a Field Experiment
Using a high-stakes field experiment conducted with a financial brokerage, we implement a novel design to separately identify two channels of social influence in financial decisions, both widely studied theoretically. When someone purchases an asset, his peers may also want to purchase it, both because they learn from his choice ("social learning") and because his possession of the asset directly affects others' utility of owning the same asset ("social utility"). We find that both channels have statistically and economically significant effects on investment decisions. These results can help shed light on the mechanisms underlying herding behavior in financial markets.
We would like to thank Sushil Bikhchandani, Aislinn Bohren, Arun Chandrasekhar, Shawn Cole, Rui de Figueiredo, Fred Finan, Uri Gneezy, Dean Karlan, Navin Kartik, Larry Katz, Peter Koudijs, Kory Kroft, Nicola Lacetera, David Laibson, Edward Leamer, Phil Leslie, Annamaria Lusardi, Kristof Madarasz, Gustavo Manso, Ted Miguel, Kris Mitchener, Adair Morse, Paul Niehaus, Andrew Oswald, Yona Rubinstein, Andrei Shleifer, Ivo Welch, as well as numerous seminar participants for helpful comments and suggestions. Juliana Portella provided excellent research assistance. We also thank the Garwood Center for Corporate Innovation, the Russell Sage Foundation and UCLA CIBER for financial support. Finally, we thank the management and staff of the cooperating brokerage firm for their efforts during the implementation of the study. There was no financial conflict of interest in the implementation of the study; no author was compensated by the partner brokerage or by any other entity for the production of this article. The views expressed herein are those of the authors and do not necessarily reflect the views of the National Bureau of Economic Research.
“Understanding Mechanisms Underlying Peer Effects: Evidence from a Field Experiment on Financial Decisions” (with Florian Ederer, Bruno Ferman, and Noam Yuchtman) Econometrica, 82(4): 1273-1301 (2014)