TY - JOUR AU - Choi,James J. AU - Laibson,David AU - Madrian,Brigitte C. AU - Metrick,Andrew TI - Consumption-Wealth Comovement of the Wrong Sign JF - National Bureau of Economic Research Working Paper Series VL - No. 10454 PY - 2004 Y2 - April 2004 UR - http://www.nber.org/papers/w10454 L1 - http://www.nber.org/papers/w10454.pdf N1 - Author contact info: James J. Choi Yale School of Management 135 Prospect Street P.O. Box 208200 New Haven, CT 06520-8200 E-Mail: james.choi@yale.edu David Laibson Department of Economics Littauer M-12 Harvard University Cambridge, MA 02138 Tel: 617/496-3402 Fax: 617/495-8570 E-Mail: dlaibson@gmail.com Brigitte C. Madrian John F. Kennedy School of Government Harvard University 79 JFK Street Cambridge, MA 02138 Tel: 617-495-8917 Fax: 617-496-5960 E-Mail: Brigitte_Madrian@Harvard.edu Andrew Metrick Yale School of Management 135 Prospect Street P.O. Box 208200 New Haven, CT 06520 Tel: 203/432-3069 E-Mail: metrick@yale.edu AB - Economic theory predicts that an unexpected wealth windfall should increase consumption shortly after the windfall is received. We test this prediction using administrative records on over 40,000 401(k) accounts. Contrary to theory, we estimate a negative short-run marginal propensity to consume out of idiosyncratic 401(k) capital gains shocks. These results cannot be interpreted as standard intertemporal substitution, since the idiosyncratic returns that we study do not predict future returns. Instead, our findings imply that many investors are influenced by a positive feedback effect, through which higher recent returns encourage higher short-run saving. Like any other animal, 401(k) participants appear to increase behaviors that have been associated with high rewards in the past. ER -