o       Current Working Papers

Verifiability and Group Formation in Markets [pdf], (with S. Scotchmer)


o       Publications


Sharing Risk and Ambiguity  [pdf], (with L. Rigotti), Journal of Economic Theory, 147(5), pp. 2028-2039.

Knightian Uncertainty and Moral Hazard, (with G. Lopomo and L. Rigotti), Journal of Economic Theory, 146(3), pp. 1148-1172.

Subjective Beliefs and Ex-Ante Trade  [pdf], (with L. Rigotti and T. Strzalecki), Econometrica, 76(5), pp. 1167-1190.

Determinacy and Indeterminacy of Equilibrium [pdf], The New Palgrave Dictionary of Economics, 2nd Edition.

What to Maximize if You Must   [pdf], (with A. Heifetz and Y. Spiegel), Journal of Economic Theory,  133(1), pp. 31-57.

The Dynamic Evolution of Preferences [pdf], (with A. Heifetz and Y. Spiegel), Economic Theory,  32(2), pp. 251-286.

A Prevalent Transversality Theorem for Lipschitz Functions  [pdf], Proceedings of the American Mathematical Society, 134(9), pp. 2755-2765.

Uncertainty and Risk in Financial Markets, (with L. Rigotti), Econometrica, vol. 73(1), pp. 203-243.


Quadratic Concavity and Determinacy of Equilibrium, (with B. Zame) Econometrica, vol. 70(2), pp. 631-662. earlier version (with more examples)


Uniqueness, Stability, and Comparative Statics in Rationalizable Walrasian Markets, (with D. Brown) Econometrica, vol. 68(6), pp. 1529-1540.


Determinacy of Competitive Equilibria in Economies with Many Commodities, Economic Theory, vol. 14, pp. 29-87.


Strict Monotonicity in Comparative Statics, (with A. Edlin) Journal of Economic Theory, vol. 81(1), pp. 201-219.


Strict Single Crossing and the Strict Spence-Mirrlees Condition, (with A. Edlin) Econometrica, vol. 66(6), pp. 1417-1426.


Increasing Returns in Infinite-Horizon Economics, Review of Economic Studies, vol. 64(1), pp. 73-96.


Weak and Strong Monotone Comparative Statics, Economic Theory, vol. 5(2), pp. 209-27.


Regular nonsmooth equations, Journal of Mathematical Economics, vol. 23(2), pp. 147-165.


Monotone Comparative Statics, (with P. Milgrom) Econometrica, vol. 62(1), pp. 157-80.

o        Older Working Papers

Recent Advances in Understanding Competitive Markets, March 2002

Generalized Convex Games (with P. Milgrom), August 1996

An Ordinal Theory of Games with Strategic Complementarities, June 1990