Research

 Selected Publications

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.

 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. 

 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. 

 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!   

 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

Abstract We conduct a field experiment to investigate the effects of partisan news on the 2016 Taiwan Presidential and Legislative Elections. Subjects are divided into four groups: rightist (KMT), leftist (DPP), new third-party and control, and provided with distinct partisan news articles. To ensure readership of assigned newspapers, subjects join multiple experimental sessions in which they are asked to solve quiz questions about the news articles and rewarded according to their quiz scores. We measure the effects of partisan news by comparing the reported vote choices in the 2016 Elections with subjects’ initial political preferences. We find that the leftist news articles have significantly increased the support for the DPP candidate Tsai by reinforcing the existing preferences. The articles about the third-parties have changed subjects’ voting intentions to support the new party GSD. We also find that the estimated baseline and reinforcement treatment effects are driven by undecided subjects or swing voters.

 Abstract.  Barbera and Jackson (2004) define a constitution as a pair of voting rules (f, F), where f is employed for ordinary decisions, and F is employed to choose between f and a proposed voting rule. While they study the stability of constitutions at the ex-ante stage, where agents' preferences over final outcomes are uncertain, we focus on the ex-post stage, where agents' preferences are known. We present a characterization of ex-post stable constitutions. Furthermore, we examine the robustness of this characterization to the changes in the voting environment and the relationship between ex-post stability and ex-ante stability of constitutions.


Other Research in Progress