Voting by committees under constraints

We consider social choice problems where a society must choose a subset from a set of objects. Specifically, we characterize the families of strategy-proof voting procedures when not all possible subsets of objects are feasible, and voters’ preferences are separable or additively representable.     

Voting by Successive Elimination and Strategic Candidacy

We study the impact of strategic choices of self-interested candidates of whether or not to enter an election. We focus on strategic candidacy in the context of the tree and binary voting procedures used by small groups such as committees. We offer a comprehensive analysis for the special but important case of voting by successive elimination. Strategic candidacy slightly enlarges the set of candidates that can be equilibrium outcomes relative to the traditional analysis which takes the set of candidates as fixed. Pareto-dominated candidates can be elected in equilibrium under voting by successive elimination when strategic candidacy is considered, in contrast with a fixed set of candidates. Journal of Economic Litterature Classification Numbers: D71, D72.     

Maskin's Theorem with limited veto power

We weaken the no-veto power condition of Maskin [Maskin, E.,1999. Nash equilibrium and welfare optimality. Rev. Econ. Stud. 66, 23–38] to limited veto power, and prove that any monotonic social choice rule is Nash implementable if it satisfies this weaker condition. The result is obtained by using the canonical Maskin mechanism without modification. An immediate corollary is that the weak core is Nash implementable in any coalitional game environment. An example is given to show that the strong core need not be implementable, even when it is monotonic.     

The influence of group size on distributional fairness under voting by veto

Voting by Veto [VBV], developed by Dennis C. Mueller, is a two-stage voting mechanism for committee decision making. In the first stage, every member of the committee makes a proposal. The proposals are joined with the current status quo (or another fallback option). For the second stage, a random mechanism determines the order of voting and the committee members sequentially eliminate one alternative each. After every committee member has exercised her veto, a single winning alternative remains. Game theory predicts that the equality of the resulting distribution under VBV varies with group size. Hence, decisions in two-member groups should result in highly unequal distributions of benefits. With increasing group size, however, VBV should generate more equally distributed outcomes. We examine the effect of group size under VBV in a series of laboratory experiments where groups with a varying number of members play a ‘divide the dollar game’. Our results confirm that larger groups choose more equal distributions than smaller groups. However, we also find deviations from the model's predictions. Some committees in our experiment do not select Pareto-optimal alternatives. An exploratory analysis of possible explanations suggests that individual behavior is most likely motivated by a combination of material self-interest and social preferences such as reciprocity and fairness.     

Voting on meritocracy

This paper considers a setting where a resource such as education budget is to be distributed among agents. The latter differ in their ability to make use of the resource, and the issue is that of determining the allocation rule whereby the individual shares of the resource (may) depend on their relative efforts of obtaining it. The paper's focus is on endogenous determination, through voting, of the degree of meritocracy in the resource allocation system, which determines the marginal productivity of one's effort. It is found that a meritocratic system is expected to be supported by highly productive individuals and opposed by those with low productivity. When the decision making becomes less elitist and involves broader participation of population groups the support for meritocracy decreases.     

Voting with abstention

Most voting models in the literature neglect abstention, but is such a simplification justified? I investigate this question in a model with outside pressure on voters. For sequential voting (e.g., roll call votes), with and without an abstention option, there is a unique subgame perfect equilibrium, which implies that true majorities always succeed. Abstention can be an equilibrium strategy for some voters, in particular under complex decision rules (e.g., weighted voting, double majorities). Simultaneous voting often has a unique pure strategy equilibrium but also a plethora of mixed and pure/mixed strategy equilibria. Therefore, only with equilibrium selection, can we evaluate the consequences of neglecting abstention. For equal weight voting, equilibria selected by the procedure of Harsanyi and Selten change completely with an abstention option, even if abstention itself is not or rarely used. With small enough outside pressure, however, the selected equilibrium honors true majorities in both cases.     

Voting as Communicating

This paper develops a model where voters trade-off two different motiveswhen deciding how to vote: they care about current decision-making (theyare "strategic"), but they also care about communicating theirviews about their most-preferred candidate so as to influence futureelections, by influencing other voters' opinion and/or partypositioning. In effect, voters in this model are intermediate between"strategic" and "sincere" voters of conventionalmodels in elections with more than 2 candidates. This allows us to betterinvestigate the relative efficiency of various electoral systems: our mainconclusion is that since voting is used as a communication device electoralsystems should be designed to facilitate efficient communication, e.g. by opting for 2-round systems rather than 1-round systems.     

Endogenously Weighted Voting

We define Endogenously Weighted Plurality Voting (EWPV) as the voting rule that, each individual being allowed to cast exactly one vote, selects the individual(s) who obtain(s) the greatest number of indirect votes. Endogenously Weighted Approval Voting (EWAV) selects the individual(s) who obtain(s) the greatest number of indirect votes when each individual can cast as many votes as he wants. In both cases, each individual can vote for any other individual, i.e., the set of candidates is the set of voters. In this study, we give necessary and sufficient axioms for EWPV and EWAV. We also propose a simple model where EWAV is more efficient than the traditional Approval Voting.     

Dissertation abstract: Essays on veto bargaining games

This dissertation experimentally analyzes the outcomes of multilateral legislative bargaining games in the presence of a veto player. The first essay examines veto power—the right of an agent to unilaterally block decisions but without the ability to unilaterally secure his/her preferred outcome. Using Winter’s (1996) theoretical framework, I consider two cases: urgent committees where the total amount of money to be distributed shrinks by 50% if proposals do not pass and non-urgent committees where the total amount of money shrinks by 5% if proposals do not pass. Committees with a veto player take longer to reach decisions (are less efficient) than without a veto player and veto players proposals generate less consensus then non-veto players proposals, outcomes on which the theory is silent. In addition, veto power in conjunction with proposer power generates excessive power for the veto player. This suggests that limiting veto players’ proposer rights (e.g., limiting their ability to chair committees) would go a long way to curbing their power, a major concern in committees in which one or more players has veto power. Finally, non-veto players show substantially more willingness to compromise than veto players, with players in the control game somewhere in between. I relate the results to the theoretical literature on the impact of veto power as well as concerns about the impact of veto power in real-life committees. The second essay discusses in detail the voting patterns in the veto and control games reported in the first essay. The empirical cumulative density functions of shares veto players accepted first degree stochastically dominates that of shares for the controls and the empirical cdfs of shares the controls accepted first degree stochastically dominate that of shares for non-veto players. Random effect probits support this conclusion as well. In addition, regressions imply favorable treatment of voting and proposing between non-veto players which, however, does not result in larger shares in the end. Coalition partners consistently demand more than the stationary subgame perfect Nash equilibrium share except for veto players in non-urgent committees. JEL Classification C7, D7, C78, D72 Dissertation Committee: John H. Kagel, Advisor Massimo Morelli Alan Wiseman Stephen Cosslett     

Voting on Unemployment Insurance

In this article, we ask heterogeneous agents in a dynamic general equilibrium economy to vote on the generosity of their unemployment insurance program. We observe the influence on their vote of (1) moral hazard, (2) private alternatives, and (3) changes in employment status. Agents differ in skills, employment probabilities, income prospects, and assets. For a calibration to the United States, we show that: (1) in contrast to the literature, plausible levels of moral hazard need not induce large cuts in optimal benefits. (2) Switching to private insurance is rejected for most status quo, though it would be as generous. (3) Skill groups vote as a block. For reasonable discount factors, solidarity is never broken simultaneously for more than one group.     

Voting on Majority Rules

We analyse an overlapping generations model of voting on "reform projects". These resemble investments in that they first require some investment expenditure and later payoff. Since the time during which old people get the benefit is shorter, or because older people are more wealthy and hence pay more taxes, they are more conservative (against reforms) than young people.
We show that if people vote on which majority should be required in future elections for a bill to become a law, the winning proposal specifies a supermajority. This result is very robust even if age related conflict is only one determinant among others for voting behaviour in the society.     

Voting with the wallet

The vote with the wallet is a new, emerging feature of economic participation and democracy in the globally integrated market economy. This expression identifies the pivotal role that responsible consumption and investment can play in addressing social and environmental emergencies which have been aggravated by the asymmetry of power between domestic institutions and global corporations. In this paper, we examine (both in general and by using examples drawn from the financial and non-financial sectors) how ??voting?? for producers which are at the forefront of a three-sided efficiency which reconciles the creation of economic value with social and environmental responsibility may generate contagion effects by triggering ethical imitation of traditional profit-maximizing actors, thereby enhancing the production of positive social and environmental externalities. Within this new framework, policies that reduce the search and information costs of voting with the wallet may help socioeconomic systems to exploit the bottom-up market forces of other-regarding preferences, thereby enhancing opportunities to achieve well-being with reduced top-down government intervention.     

Voting in small committees

We analyze the voting behavior of a small committee that has to approve or reject a project proposal whose return is uncertain. Members have diverse preferences: some of them want to maximize the expected value, while others have a bias towards project approval and ignore their information on the project value. We focus on the most efficient use of scarce information when members cannot communicate prior to voting, and we provide insights on the optimal composition of the committee. Our main result is that the presence of biased members can improve the voting outcome, by simplifying the strategies of unbiased members. Thus, committees with diverse members perform as well as homogeneous committees, and even better in some cases. In particular, when value-maximizing members outnumber biased members by one vote, the optimal equilibrium becomes unique.     

Voting over income taxation

A major problem of the positive theory of income taxation is to explain why statutory income tax schedules in practice are marginal-rate progressive. While it is commonly believed that this is but a simple consequence of the fact that the number of relatively poor voters exceeds that of richer voters in general, putting this contention in a voting equilibrium context is not a trivial task. We do this here in the context of nonlinear taxation and attempt to provide a formal argument in support of this heuristic claim. We first establish the existence of mixed strategy equilibria and identify certain cases in which marginal-rate progressive taxes are chosen almost surely by the political parties. Unfortunately, we also find that if the tax policy space is not artificially constrained, the support of at least one equilibrium cannot be contained within the set of marginal-rate progressive taxes.     

Convergence Results for Unanimous Voting

This paper derives a necessary condition for unanimous voting to converge to the perfect information outcome when voters are only imperfectly informed about the alternatives. Under some continuity assumptions, the condition is also sufficient for the existence of a sequence of equilibria that exhibits convergence. The requirement is equivalent to that found by Milgrom [1979, Econometrica47, 679-688] for information aggregation in single-prize auctions. An example illustrates that convergence may be reasonably fast for small committees. However, if voters have common preferences, unanimity is not the optimal voting rule. Unanimity rule makes sense only as a way to ensure minority views are respected. Journal of Economic Literature Classification Numbers: D72, D82, D44.     

Strategy-Proof Voting on Compact Ranges

Strategy-proof social choice functions are characterized for societies where the space of alternatives is any full dimensional compact subset of a Euclidean space and all voters have generalized single-peaked preferences. Our results build upon and extend those obtained for cartesian product ranges by Border and Jordan (1983). By admitting a large set of non-Cartesian ranges, we give a partial answer to the major open question left unresolved in this pioneering article. We prove that our class is composed by generalized median voter schemes which satisfy an additional condition, called the intersection property [Barberà, Massó, and Neme (1997)].Journal of Economic LiteratureClassification Number: D71.     

Voting over income tax schedules

In many voting situations, preferences over options may fail to be single-peaked. This is especially true when options consist of different amounts of a good which is provided through distortionary taxation. In this paper, voting over linear income tax schedules is considered. Although preferences may fail to be single-peaked, a choice set is shown to exist when only mild restrictions are imposed. For many choices in the public domain, the conditions required for this result are likely to be satisfied.     

Voting as a signaling device

In this paper, citizens vote in order to influence the election outcome and in order to signal their unobserved characteristics to others. The model is one of rational voting and generates the following predictions: (i) The paradox of not voting does not arise, because the benefit of voting does not vanish with population size. (ii) Turnout in elections is positively related to the importance of social interactions. (iii) Voting may exhibit bandwagon effects and small changes in the electoral incentives may generate large changes in turnout due to signaling effects. (iv) Signaling incentives increase the sensitivity of turnout to voting incentives in communities with low opportunity cost of social interaction, while the opposite is true for communities with high cost of social interaction. Therefore, the model predicts less volatile turnout for the latter type of communities.