NATIONAL BUREAU OF ECONOMIC RESEARCH
NATIONAL BUREAU OF ECONOMIC RESEARCH

NBER Working Papers by Gabriel Weintraub

Contact and additional information for this authorAll papers and publicationsWorking Papers onlyWorking Papers with publication info

Working Papers

August 2013Oblivious Equilibrium for Concentrated Industries
with C. Lanier Benkard, Przemyslaw Jeziorski: w19307
This paper explores the application of oblivious equilibrium to concentrated industries. We define an extended notion of oblivious equilibrium that we call partially oblivious equilibrium (POE) that allows for there to be a set of "dominant firms'', whose firm states are always monitored by every other firm in the market. We perform computational experiments that show that POE are often close to MPE in concentrated industries with characteristics similar to real world industries even when OE are not. We derive error bounds for evaluating the performance of POE when MPE cannot be computed. Finally, we demonstrate an important trade-off facing empirical researchers between implementing an equilibrium concept that is computationally light in a richer economic model, and implementing MPE in...
August 2010Industry Dynamics: Foundations For Models with an Infinite Number of Firms
with C. Lanier Benkard, Benjamin Van Roy: w16286
This paper explores the connection between three important threads of economic research offering different approaches to studying the dynamics of an industry with heterogeneous firms. Finite models of the form pioneered by Ericson and Pakes (1995) capture the dynamics of a finite number of heterogeneous firms as they compete in an industry, and are typically analyzed using the concept of Markov perfect equilibrium (MPE). Infinite models of the form pioneered by Hopenhayn (1992), on the other hand, consider an infinite number of infinitesimal firms, and are typically analyzed using the concept of stationary equilibrium (SE). A third approach uses oblivious equilibrium (OE), which maintains the simplifying benefits of an infinite model but within the more realistic setting of a finite model....
December 2005Markov Perfect Industry Dynamics with Many Firms
with C. Lanier Benkard, Ben Van Roy: w11900
We propose an approximation method for analyzing Ericson and Pakes (1995)-style dynamic models of imperfect competition. We develop a simple algorithm for computing an ``oblivious equilibrium,'' in which each firm is assumed to make decisions based only on its own state and knowledge of the long run average industry state, but where firms ignore current information about competitors' states. We prove that, as the market becomes large, if the equilibrium distribution of firm states obeys a certain ``light-tail'' condition, then oblivious equilibria closely approximate Markov perfect equilibria. We develop bounds that can be computed to assess the accuracy of the approximation for any given applied problem. Through computational experiments, we find that the method often generates useful app...

Contact and additional information for this authorAll papers and publicationsWorking Papers onlyWorking Papers with publication info

 
Publications
Activities
Meetings
Data
People
About

Support
National Bureau of Economic Research, 1050 Massachusetts Ave., Cambridge, MA 02138; 617-868-3900; email: info@nber.org

Contact Us