Doctoral Student

Assaf Romm

Born and raised in Israel. Studied at the Hebrew University of Jerusalem, Israel. Holds a BSc in Math, Economics and Amirim program, and an MA in Economics and the Center for the study of Rationality's program. Currently studying for PhD in the Business Economics program.

  1. Information Effects of Jump Bidding in English Auctions (with Dror Lellouche)

    by Assaf Romm

    Under what circumstances might a bidder find it rational to raise the current offer by a substantial factor instead of making just a small increase above the highest bid? This paper aims to answer this question by exploring the implications of jump bidding over the information sets available to the bidders. Our motivation is to find whether hiding the information about other players' signals might be beneficial for one of the bidders. We first show that it is better for the auctioneer to set a reservation price rather than "jump" to the starting price. We then prove that in a very general setting and when bidders are risk-neutral there exist no equilibrium with jump bidding (in non-weakly dominated strategies). Finally, we demonstrate that jump bidding might be a rational consequence of risk aversion, and analyze the different effects at work. 

  2. What Happens when Agents Join Many-to-One Matching Market?

    by Assaf Romm

    In their seminal book about matching theory, Roth and Sotomayor (1990) discuss (among other things) what happens in a one-to-one matching market when a new woman joins it. An elegant result shows that in this scenario there exists a non-empty set of men (related to a set of women) each of whom is strictly better off (worse off) under any stable matching in the new market, compared to any stable matching in the old market. This paper explores several extension to this theorem. The main results are that this theorem generalizes for the case of many-to-one matching when a hospital joins the market, but not when a doctor joins it. Furthermore, in the case of generalized matching with contracts a weaker form of the theorem is demonstrated.