TY - JOUR AU - Veldkamp,Laura AU - Wolfers,Justin TI - Aggregate Shocks or Aggregate Information? Costly Information and Business Cycle Comovement JF - National Bureau of Economic Research Working Paper Series VL - No. 12557 PY - 2006 Y2 - October 2006 UR - http://www.nber.org/papers/w12557 L1 - http://www.nber.org/papers/w12557.pdf N1 - Author contact info: Laura Veldkamp Stern School of Business New York University 44 W Fourth Street,Suite 7-77 New York, NY 10012 Tel: 212/998-0527 Fax: 212/995-4218 E-Mail: lveldkam@stern.nyu.edu Justin Wolfers Department of Economics University of Michigan 611 Tappan St Lorch Hall #319 Ann Arbor, MI 48104 Tel: 734-764-2447 E-Mail: jwolfers@umich.edu AB - Synchronized expansions and contractions across sectors define business cycles. Yet synchronization is puzzling because productivity across sectors exhibits weak correlation. While previous work examined production complementarity, our analysis explores complementarity in information acquisition. Because information about future productivity has a high fixed cost of production and a low marginal cost of replication, sectors can share the cost to forecast their sector-specific productivity. Sectors with common, aggregate information make highly correlated productions choices. By filtering out sector-specific shocks and transmitting aggregate ones, information markets amplify business-cycle comovement. ER -