Moulin obtained his undergraduate degree from the Ecole Normale Superieure in Paris in 1971 and his doctoral degree in Mathematics at the University of Paris in 1975 with a thesis on zero-sum games, which was published in French at the Mémoires de la Société Mathématique de France and in English in the Journal of Mathematical Analysis and its Applications. On 1979, he published a seminal paper in Econometrica introducing the notion of dominance solvable games. Dominance solvability is a solution concept for games which is based on an iterated procedure of deletion of dominated strategies by all participants. Dominance solvability is a stronger concept than Nash equilibrium because it does not require ex-ante coordination. Its only requirement is iterated common knowledge of rationality. His work on this concept was mentioned in Eric Maskin's Nobel Prize Lecture. One year later he proved an interesting result concerning the famous Gibbard-Satterthwaite Theorem, which states that any voting procedure on the universal domain of preferences whose range contains more than two alternatives is either dictatorial or manipulable. Moulin proved that it is possible to define non-dictatorial and non-manipulable social choice functions in the restricted domain of single-peaked preferences, i.e. those in which there is a unique best option, and other options are better as they are closer to the favorite one. Moreover, he provided a characterization of such rules. This paper inspired a whole literature on achieving strategy-proofness and fairness on restricted domains of preferences. Moulin is also known for his seminal work incost sharing and assignment problems. In particular, jointly with Anna Bogomolnaia, he proposed the probabilistic-serial procedure as a solution to the fair random assignment problem, which consists of dividing several goods among a number of persons. Probabilistic serial allows each person to "eat" her favorite shares, hence defining a probabilistic outcome. It always produces an outcome which is unambiguously efficient ex-ante, and thus has a strong claim over the popular random priority. The paper was published in 2001 in the Journal of Economic Theory. By summer of 2016, the article had 395 citations. He has been credited as the first proposer of the famous beauty contest game, also known as the guessing game, which shows that players fail to anticipate strategic behavior from other players. Experiments testing the equilibrium prediction of this game started the field of experimental economics. In July 2018 Moulin was elected Fellow of the British Academy.
Coauthors
Moulin has published work jointly with Matthew O. Jackson, Scott Shenker, and Anna Bogomolnaia, among many other academics.