**Research**

o Current
Working Papers

Verifiability
and Group Formation in Markets [pdf], (with

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, 2^{nd} 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