Working Papers

We propose a model of decision-making based on Markovian exploration of a choice set. It is inspired by experimental evidence that decision makers search sequentially by making stochastic pairwise comparisons. The model allows us to analyze the impact of a variety of interventions on final choices and to infer unobservable characteristics of the agent. We examine how choice can be influenced by the first fixation, comparability restrictions, time pressure, and by adding a dominated alternative. We show that the long-run choices of an agent are not susceptible to manipulation if the Markovian model is reversible and that such choices are consistent with the well-known Luce model. Further, we identify conditions on the long-run choice data that reveal the agent's consideration set and comparability restrictions. Finally, we show how one can isolate the effect of utility from salience on choice probability.

July 2022 (First version: April 2018)

Ordinal random utility models (RUMs) are based on the assumption that stochastic choices result from decision makers’ fluctuating preferences. In this paper we examine whether random choice behavior reveals the properties of the underlying preferences of the agent. We show that stochastic choice data which satisfies two simple properties called regularity and strong centrality can only be rationalized with RUMs that are single-peaked. We obtain analogous results for single-dipped RUMs and a more general class of RUMs that we call peak-pit on a line. Finally, we show that the peak-pit on a line domain is nested in the domains of triple-wise value-restricted and peak-monotone preferences and demonstrate how these properties could be revealed from choice data.

Published Papers

with Christian Ewerhart (2020). Games and Economic Behaviour, 123, pp. 182-206

This paper studies fictitious play in networks of noncooperative two-person games. We show that continuous-time fictitious play converges to the set of Nash equilibria if the overall n-person game is zero-sum. Moreover, the rate of convergence is 1/t, regardless of the size of the network. In contrast, arbitrary n-person zero-sum games with bilinear payoff functions do not possess the continuous-time fictitious-play property. As extensions, we consider networks in which each bilateral game is either strategically zero-sum, a weighted potential game, or a two-by-two game. In those cases, convergence requires a condition on bilateral payoffs or, alternatively, that the network is acyclic. Our results hold also for the discrete-time variant of fictitious play, which implies, in particular, a generalization of Robinson's theorem to arbitrary zero-sum networks. Applications include security games, conflict networks, and decentralized wireless channel selection.

Work in Progress

Clearance Voting

with Hans Gersbach