Research Interests: Political Economy, Formal Theory
Weighted Voting and Information Acquisition in Committees (2013)
In a weighted voting system, votes are assigned based on predetermined criteria, such as population for the decision-making at the EU Council, shares at shareholder meetings, and financial contribution at the IMF and the World Bank. The criterion is typically unrelated to the voters' ability to make a correct judgment. Do these unequal decision power distributions undermine the accuracy of group decisions? The goal of this paper is to analyze how the distribution of votes affects the accuracy of group decisions. I introduce an information aggregation model in which voters are identical except for voting shares. If the information is free, the accuracy of group decisions is always higher under unweighted majority rule than any weighted majority rules. When acquiring information is costly, by contrast, I show that the accuracy of group decisions may be higher under some weighted majority rules than under unweighted majority rule. This may justify giving someone greater decision power even if the person is no more capable than others. More generally, I characterize the equilibrium and find the optimal weight distribution to maximize the accuracy of group decisions. Asymmetric weight distributions may be optimal when the cost of improving signal is moderately high.
Local Gossip and Intergenerational Family Transfers: Comparative Political Economy of Welfare Provision (2012)
In the era of population aging, families are an important source of welfare provision. Individuals provide education and nutrition to their children and nursing care to their elderly parents. Why do families work as a welfare provider? Why are generous transfers made in some families and not in others? This paper explains how these intergenerational "contracts" can be sustained and argues that differences in intergenerational cooperation are due to variation in neighbors' gossiping.
My analysis posits game-theoretical models of overlapping generations in which breadwinners make transfers to their parents and children. A novel feature of my model is that there is a local community that may supply information about its members' past behaviors. I find that gossip plays a crucial role as information for sustaining the intergenerational cooperation within families. More specifically, an efficient level of intergenerational transfers can be sustained if and only if neighbors gossip about each other. My findings are consistent with the known empirical evidence that social pressure facilitates people to take care of their elderly parents.
Legislative Committees as Information Intermediaries: A Unified Theory of Committee Selection and Amendment Rules (2013), with Attila Ambrus, Eduardo Azevedo, Yuichiro Kamada, Journal of Economic Behavior & Organization, 94: 103-115.
This paper contributes to understanding the role of interest groups in legislative decision-making, and offerrs an explanation to two widely discussed puzzles concerning the legislative process: why legislative bodies sometimes tie their own hands by delegating power to specialized committees, and why committees consist of preference outliers. In our model, the legislature has to collect information from a strategic lobbyist. Depending on the lobbyist’s bias, the legislature either wants to delegate power to a committee aligned with the lobbyist, or retain power but communicate with the lobbyist through an adversely biased committee.
Supplementary Note to: Legislative Committees as Information Intermediaries: A Unified Theory of Committee Selection and Amendment Rules (2012), with Attila Ambrus, Eduardo Azevedo, Yuichiro Kamada
A Theory of Hung Juries and Informative Voting (2010), with Fuhito Kojima, Games and Economic Behavior.
This paper investigates a jury decision when hung juries and retrials are possible. When jurors in subsequent trials know that previous trials resulted in hung juries, informative voting cannot be an equilibrium regardless of voting rules unless the probability that each juror receives the correct signal when the defendant is guilty is identical to the one when he is innocent. Thus, while Coughlan (2000) claims that mistrials facilitate informative voting, our result shows that such an assertion holds only in limited circumstances.
Economic Development and Political Development (undergraduate/graduate, summer 2015 at Waseda University)
POLISCI 241A: An Introduction to Political Economy of Development (undergraduate, fall 2014)