Diagnostic Expectations and Stock Returns

68 Pages Posted: 25 Sep 2017

See all articles by Pedro Bordalo

Pedro Bordalo

University of Oxford - Said Business School

Nicola Gennaioli

Bocconi University - Department of Finance; Bocconi University - IGIER - Innocenzo Gasparini Institute for Economic Research

Rafael La Porta

Dartmouth College - Tuck School of Business; National Bureau of Economic Research (NBER)

Andrei Shleifer

Harvard University - Department of Economics; National Bureau of Economic Research (NBER); European Corporate Governance Institute (ECGI)

Date Written: September 2017

Abstract

We revisit La Porta’s (1996) finding that returns on stocks with the most optimistic analyst long term earnings growth forecasts are substantially lower than those for stocks with the most pessimistic forecasts. We document that this finding still holds, and present several further facts about the joint dynamics of fundamentals, expectations, and returns for these portfolios. We explain these facts using a new model of belief formation based on a portable formalization of the representativeness heuristic. In this model, analysts forecast future fundamentals from the history of earnings growth, but they over-react to news by exaggerating the probability of states that have become objectively more likely. Intuitively, fast earnings growth predicts future Googles but not as many as analysts believe. We test predictions that distinguish this mechanism from both Bayesian learning and adaptive expectations, and find supportive evidence. A calibration of the model offers a satisfactory account of the key patterns in fundamentals, expectations, and returns.

Suggested Citation

Bordalo, Pedro and Gennaioli, Nicola and La Porta, Rafael and Shleifer, Andrei, Diagnostic Expectations and Stock Returns (September 2017). NBER Working Paper No. w23863, Available at SSRN: https://ssrn.com/abstract=3042437

Pedro Bordalo (Contact Author)

University of Oxford - Said Business School ( email )

Park End Street
Oxford, OX1 1HP
Great Britain

Nicola Gennaioli

Bocconi University - Department of Finance ( email )

Via Roentgen 1
Milano, MI 20136
Italy

Bocconi University - IGIER - Innocenzo Gasparini Institute for Economic Research ( email )

Via Roentgen 1
Milan, 20136
Italy

Rafael La Porta

Dartmouth College - Tuck School of Business ( email )

Hanover, NH 03755
United States

National Bureau of Economic Research (NBER)

1050 Massachusetts Avenue
Cambridge, MA 02138
United States

Andrei Shleifer

Harvard University - Department of Economics ( email )

Littauer Center
Cambridge, MA 02138
United States
617-495-5046 (Phone)
617-496-1708 (Fax)

HOME PAGE: http://www.economics.harvard.edu/~ashleife/

National Bureau of Economic Research (NBER)

1050 Massachusetts Avenue
Cambridge, MA 02138
United States

European Corporate Governance Institute (ECGI)

c/o the Royal Academies of Belgium
Rue Ducale 1 Hertogsstraat
1000 Brussels
Belgium

HOME PAGE: http://www.ecgi.org

Here is the Coronavirus
related research on SSRN

Paper statistics

Downloads
73
Abstract Views
1,065
rank
349,993
PlumX Metrics