Selected Publications
"On the (Robust) Ex-post Stability of Constitutions" with Daeyoung Jeong , Journal of Public Economic Theory, 26, (2024), e12707
Can we completely characterize the stable constitutions? Yes, we can, at least in ex-post set-ups where the information regarding preferences of voters is revealed. A constitution (f,F) is ex-post stable if and only if a winning coalition under the base rule F should be both a winning and veto coalition under the regular rule f.
“Stable Constitutions”, with Daeyoung Jeong, Games and Economic Behavior, 142, (2023), 794-811.
Which voting rules would stably survive if a society change its own rules? We define and examine the concepts of interim/ex-post stability, where by agents' preferences over the final outcomes are privately/publicly known when they decide on changing a voting rule. We try to characterize a set of interim stable constitutions.
"Unanimity and Local Incentive Compatibility in Sparsely Connected Domains", with Miho Hong , Social Choice and Welfare, 61, (2023), 385–411.
What are the implications of imposing unanimity (an extremely weak and desirable condition) on local incentive compatible social choice functions in broad domains (sparsely connected domains)? Tops-onlyness and full incentive compatibility. Furthermore, we completely characterize dictatorial domains.
“Ordinal versus Cardinal Voting Rules: A Mechanism Design Approach”, Games and Economic Behavior, 104 (2017), 350-371.
It is easy to design a cardinal voting rule which improves ordinal voting rules that use only the ranking information over the alternatives. But can we design such a cardinal rule satisfying incentive compatibility as well? The answer is positive, but only in a restricted environment.
"On the Self-(In)Stability of Weighted Majority Rules" with Yaron Azrieli, Games and Economic Behavior, 100 (2016), 376-389.
A voting rule f is self-stable if any alternative rule g does not have sufficient support to replace f, where the decision between f and g is based on the rule f itself. What about the self-stability of weighted majority rules? It turns out that only a few of weighted majority rules are self-stable!
“Pareto Efficiency and Weighted Majority Rules”, with Yaron Azrieli, International Economic Review, 55 (2014), 1067-1088.
What are the Pareto efficient and incentive compatible decision rules at interim (or ex-ante) stage? We show that a decision rule is incentive compatible and Pareto efficient at interim stage if and only if it is a weighted majority rule.
Working Papers
“Bitcoin Mining Game: What Is the Role of Risk-averse Small Miners? ”, with Jiuk Choi (under review)
Abstract: We model a sequential Bitcoin mining game between miners that incorporates two specific features of the miners: heterogeneity in cost structures and risk attitudes stemming from differences in scale. By comparing equilibria under scenarios in which small miners are risk-neutral versus risk-averse, we investigate the effect of small miners' risk-averse attitudes on the Bitcoin mining game. We find that when small miners are risk-averse, return-related factors, such as the expected value and volatility of Bitcoin prices, influence risk-neutral large miners. This contrasts with the risk-neutral small miner case, where large miners do not care about these factors. Notably, large miners participate less actively in the mining market even though the expected value of Bitcoin price rises, unlike in the risk-neutral case, where their decisions remain unchanged. Welfare analysis reveals that the social cost of Bitcoin mining has been overestimated while its benefit has been underestimated.
"Anonymous voting in a heterogeneous society", with Yaron Azrieli and Ritesh Jain (under review)
Abstract: We study the design of voting mechanisms in a binary social choice environment where agents' cardinal valuations are independent but not necessarily identically distributed. The mechanism must be anonymous - the outcome is invariant to permutations of the reported values. We show that if there are two agents then expected welfare is always maximized by an ordinal majority rule, but with three or more agents there are environments in which cardinal mechanisms that take into account preference intensities outperform any ordinal mechanism.
Abstract: Under independent generic beliefs, unanimity and ordinal Bayesian incentive compatibility (OBIC) imply dictatorship. We study where this conclusion first fails as genericity is relaxed, in the minimal nontrivial environment of two voters, three alternatives, and the unrestricted domain of strict preferences. We obtain an exact classification of the exceptional balance relations and the mechanisms they support, without imposing any further symmetry on the ranking distribution. Among the 301 reduced genericity relations, only pairwise-balance relations—those equating the probabilities that two alternatives defeat a common benchmark—can support a non-dictatorial unanimous deterministic OBIC rule when exactly one marginal satisfies a single genericity relation and the other remains generic. In this one-sided case, exactly five rules are OBIC, including three non-dictatorial unilateral agenda mechanisms. Under i.i.d. beliefs, the only additional relation type is top balance—equality of first-choice probabilities for two alternatives—which supports a unique non-dictatorial agreement-or-default rule. These two exceptional relation types operate through distinct approval and agreement channels, respectively, and both channels persist in larger electorates.
Other Research in Progress
"Vote Trading with Farsighted Stability", with Jiuk Choi and Sungrae Kim
Dormant Papers