Ali Ozkes

Postdoctoral Fellow

Aix-Marseille School of Economics

E-mail: ozkesali [at]

Curriculum Vitae - pdf 

Research Interests:  
Behavioral Game Theory • Experiments
Social Choice Theory • Political Economy


with R. Sanver, Economics Letters (2017), 153:20-22

with J. Lainé and R. Sanver, Social Choice and Welfare (2016),  46/1:157-182

with B. Can and T. Storcken, Mathematical Social Sciences (2015), 78:76-79

Working Papers:

4. The effects of cognitive skills, communication, and strategic environment on cooperation
with N. Hanaki

New version coming soon.

with Y. Koriyama

Abstract: An information aggregation problem of the Condorcet Jury Theorem is considered with cognitive hierarchy models in which players best respond holding heterogeneous beliefs on the cognitive level of the other players. Whether the players are aware of the presence of opponents at their own cognitive level turns out to be a key factor for asymptotic properties of the deviation from Nash behavior, and thus for asymptotic efficiency of the group decision. Our laboratory experiments provide evidence for the self-awareness condition. We obtain an analytical result showing that the difference from the standard cognitive hierarchy models arises when the best-reply functions are asymptotically expanding.

with B. Can and T. Storcken

Abstract: We provide axiomatic characterizations for measures of polarization in profiles of preferences that are represented as rankings of alternatives. Polarization is seen as the extent to which opinions are opposed. We provide characterizations for an extension of this simple intuition on the pairs of alternatives to the cases with more than two alternatives. Our primary generalization allows for different treatment among issues, i.e., pairs of alternatives. Secondly, we show that the characterization result continues to hold when preferences are allowed to attain indifferences. Finally, we show that we can also impose a domain restriction that only allows for single-peaked preferences and retain our characterization. Our results point to a fundamental feature of measures on profile of preferences that are based on pairwise comparisons of alternatives.

with R. Sanver

Abstract: We revisit the neutrality requirement in social choice theory. We propose a weakening of the standard neutrality condition, by allowing for different procedural treatment for different alternatives while entailing that alternatives enjoy same ex-ante possibility to be chosen. We compare these two conditions theoretically and computationally. Furthermore, we explore social choice problems in which this weakening resolves impossibilities that stem from a fundamental tension between neutrality and anonymity. Finally, we show that in certain social choice problems, this weakening provides an immediate refinement of anonymous, neutral, and Pareto optimal social choice rules towards retaining resoluteness.

with U. Ozdemir

Abstract: We adapt an axiomatically derived measure of polarization due to Esteban and Ray (1994) to measure polarization of political preferences. Previous work used different measures such as variance, kurtosis, Cronbach's alpha, median distance to median, and the mean distance between groups. Yet, none of these measures are theoretically connected to a notion of polarization and this is one of the reasons why previous literature is far from a consensus on the trend of mass polarization in the United States. Although the introduction of the current one is in the lieu of income inequality measurement, it is conceptually suitable for preferential polarization as well. This paper offers a methodology for that purpose, alongside scrutinizing previously employed measures. Furthermore, we employ the Aldrich-McKelvey Scaling to correct for differential-item functioning in estimating ideal points of the individuals and Poole's Scaling as a dimension reduction technique. We use the American National Election Survey data for years between 1984 - 2012 to implement the theory referred to in the paper. Finally, we compare our results on public opinion with congressional polarization. Our findings suggest that, overall, this period cannot be characterized as a period with continuous polarization in the American public, although there are significant changes within some sub-periods and on some issues. Congress, on the other hand, is shown to exhibit high level of polarization. 

In Progress