Non-consequentialist voting

Standard theory assumes that voters’ preferences over actions (voting) are induced by their preferences over electoral outcomes (policies, candidates). But voters may also have non-consequentialist (NC) motivations: they may care about how they vote even if it does not affect the outcome. When the likelihood of being pivotal is small, NC motivations can dominate voting behavior. To examine the prevalence of NC motivations, we design an experiment that exogenously varies the probability of being pivotal yet holds constant other features of the decision environment. We find a significant effect, consistent with at least 12.5 percent of subjects being motivated by NC concerns.     

Natural disasters and electoral outcomes

Natural disasters are good examples of catastrophic events that may affect vote decisions. In this study, we analyze how the occurrence of earthquakes changes voters' behavior at municipal elections and which channels drive this change, focusing in particular on the role of media exposure. We exploit data from 13,338 municipal electoral cycles where incumbents seek reelection between 1993 and 2015 in Italy. We apply a difference-in-difference strategy with time and cities fixed effect to the probability of reelection and vote share using three different control groups: the universe of municipalities, a sub-sample of neighboring municipalities, and a sub-sample of municipalities identified by a one-to-one nearest-neighbor propensity score matching procedure. We find that the occurrence of destructive earthquakes significantly increases the incumbent mayors’ chance of being reelected and their vote share. We argue that this result is driven by the incumbent mayor advantage in offering recovery from disaster damages combined with a higher visibility on the media in the aftermath of the disaster. Thus, the mediatic relevance of earthquake occurrence may bias voters towards the incumbent.     

A characterization of strategic complementarities

I characterize games for which there is an order on strategies such that the game has strategic complementarities. I prove that, with some qualifications, games with a unique equilibrium have complementarities if and only if Cournot best-response dynamics has no cycles; and that all games with multiple equilibria have complementarities. As applications of my results, I show that: (1) generic 2×2 games either have no pure-strategy equilibria, or have complementarities; (2) generic two-player finite ordinal potential games have complementarities.     

Non-cooperative solutions for estate division problems

In an estate division problem an estate has to be divided among several players whose total entitlement to the estate exceeds its size. This paper extends the non-cooperative approach through a claim game, as initiated by O?Neill (1982), by allowing players to put multiple claims on the same part of the estate, and by considering the case where individual entitlements may exceed the estate. A full characterization of the set of Nash equilibria of the claim game is obtained both for restricted estate division problems, where individual entitlements do not exceed the estate, and for the general case. Variations on the claim game are considered, which result in proportional division in equilibrium.     

Would letting people vote for multiple candidates yield policy moderation?

We investigate whether letting people vote for multiple candidates would yield policy moderation. We do so in a setting that takes three key features of elections into account, namely, strategic voting, endogenous candidacy and policy motivation on the part of the candidates. We consider two classes of voting rules. One class consists of the voting rules where each voter casts several equally-weighed votes for the different candidates. The other class consists of the voting rules where each voter rank-orders the candidates. We identify conditions under which these voting rules yield policy moderation. We also show that these voting rules may yield policy extremism instead of policy moderation if one (or several) of the conditions is not satisfied! Finally, we find that amongst these voting rules the extent of policy moderation is maximal under the Borda Count if we consider only equilibria where all candidates are serious contenders. However, this result does not carry over to spoiler equilibria, where Approval Voting can yield more moderate policy outcomes than the Borda Count.     

Voting blocs, party discipline and party formation

I study the strategic incentives to coordinate votes in an assembly. Coalitions form voting blocs, acting as single players and affecting the policy outcome. In an assembly with two exogenous parties I show how the incentives to accept party discipline depend on the types of the agents, the sizes of the parties, and the rules the blocs use to aggregate preferences. In a game of fully endogenous party formation, I find sufficient conditions for the existence of equilibria with one bloc, two blocs, and multiple blocs.     

Electoral Thresholds as Coordination Devices

In this paper, we study one‐person–one‐vote parliamentary elections where voters care both about the winner of elections and about the composition of the parliament. Parties enter the parliament if and only if their vote share exceeds some predetermined threshold. We show that equilibria generically exist in which all parties obtain a non‐degenerate vote‐share and, perhaps more importantly, we show that the size of the electoral threshold acts as a coordination device, which crucially affects the win prospects of the Condorcet winner party. In particular, we argue that the win prospects of the Condorcet winner party decrease with the size of the entry threshold.     

Dynamic legislative decision making when interest groups control the agenda

We consider dynamic decision making in a legislature, in which in each period legislators vote between the status quo (previous period?s policy) and a new bill. However, the agenda formation process is captured by interest groups, that is, the new bill on the agenda is determined by an all-pay auction among these groups. We show that convergence to the median voter of the legislature arises if interest groups are patient enough but not necessarily otherwise. We characterize the bound on the speed of convergence in a family of stationary equilibria in which policy bounces between right-wing and left-wing policies. We also show that convergence may be faster if organized interest groups represent only one side of the policy space, e.g., when only business and not consumer interests are organized.     

Strategic network formation through peering and service agreements

We introduce a game theoretic model of network formation in an effort to understand the complex system of business relationships between various Internet entities (e.g., Autonomous Systems, enterprise networks, residential customers). In our model we are given a network topology of nodes and links where the nodes act as the players of the game, and links represent potential contracts. Nodes wish to satisfy their demands, which earn potential revenues, but may have to pay their neighbors for links incident to them. We incorporate some of the qualities of Internet business relationships, including customer–provider and peering contracts. We show that every Nash equilibrium can be represented by a circulation flow of utility with certain constraints. This allows us to prove bounds on the prices of anarchy and stability. We also focus on the quality of equilibria achievable through centralized incentives.     

Rationing and rationality

This paper investigates a simple three-good two-sector macromodel with fixed prices. In order to omit any ad hoc assumptions about the market outcomes we analyse the model as a game played by (fully) rational players. Whereas the notion of rationality underlying the concept of Nash equilibria implies a multiplicity of solutions (with different trades and different excess demands) the refined notion of uniformly perfect equilibria yields uniqueness. Interestingly, the unique solution implies excess demands differing from previously discussed suggestions. Accordingly, the amount of involuntary unemployment may here be different from those in former models even though transactions are the same. In principle, the model provides a reasonable basis to interpret the magnitude of excess demands, what seems important since excess demands serve as signals not only for markets but also for policy makers.     

Intergovernmental transfers and political competition measured by pivotal probability - Evidence from Hungary

I estimate the effects of political competition on the allocation of intergovernmental transfers to Hungarian municipalities between 1998 and 2006. The intergovernmental transfers were intended to finance schooling, elder care, and administrative needs in municipalities. Rather than use closeness of the dominant blocks' vote share, which is the standard measure of political competition, I instead employ (Myerson, 2000)'s pivotal probabilities, calculated at the municipality level. As a result, the number of voters, in addition to the vote difference, is taken into account when describing political competition at the municipal level. I argue that under mixed-member proportional systems, as well as under proportional systems in general, pivotal probability reflects the political reality better than closeness can. I find evidence that swing municipalities in villages are targeted and, ceteris paribus, that poorer regions receive larger transfer amounts than other areas.     

The dynamic instability of dispersed price equilibria

We adopt an evolutionary framework to explain price dispersion as a time varying phenomenon. By developing a finite strategy analogue of the Burdett and Judd (1983) price dispersion model, we show that all dispersed price equilibria are unstable under the class of perturbed best response dynamics. Instead, numerical simulations using the logit dynamic show that price dispersion manifests itself as a limit cycle. We verify that limit cycles persist even when the finite strategy model approaches the original continuous strategy model. For a particularly simple case of the model, we prove the existence of a limit cycle.     

Determinacy of equilibrium outcome distributions for zero sum and common utility games

We show the generic finiteness of probability distributions induced on outcomes by the Nash equilibria in two player zero sum and common interest outcome games.     

Nonminimal product differentiation as a bargaining outcome

It is well known that in a duopoly model of product choice with quadratic transportation cost, the firms locate at the extreme endpoints of the market. Jehiel (1992, Int. J. Ind. Organ, 10, 633–641) has examined this model in an infinite horizon setting where in the initial period the firms choose location and in subsequent periods charge the Nash bargaining solution prices. Then, in the unique equilibrium both firms locate at the center of the market. This paper examines the case when the firms instead charge the prices determined by either the egalitarian bargaining solution or the Kalai–Smorodinski bargaining solution. It is shown that central agglomeration is an equilibrium. Furthermore, there is a continuum of symmetric equilibria in addition where the firms locate apart from each other. So the products are not necessarily minimally differentiated. Thus different bargaining solutions provide quite different outcomes.     

How to win a large election

We consider the optimization problem of a campaign trying to win an election when facing aggregate uncertainty, where agentsʼ voting probabilities are uncertain. Even a small amount of uncertainty will in a large electorate eliminate many of counterintuitive results that arise when voting probabilities are known. In particular, a campaign that can affect the voting probabilities of a fraction of the electorate should maximize the expected difference between its candidateʼs and the opposing candidateʼs share of the fractionʼs potential vote. When a campaign can target only finitely many voters, maximization of the same objective function remains optimal if a convergence condition is satisfied. When voting probabilities are certain, this convergence condition obtains only at knife-edge combinations of parameters, but when voting probabilities are uncertain the condition is necessarily satisfied.     

An implementation of the Owen value

We present an implementation of the Owen value (Owen, 1977, Essays in Mathematical Economics and Game Theory, pp. 76–88), inspired by the bidding mechanism introduced by Pérez-Castrillo and Wettstein (2001, J. Econ. Theory 100, 274–294). The idea is the following: first players of each coalition play the bidding mechanism trying to obtain the resources of the coalition. Later, players who obtained the resources play the bidding mechanism in order to share the surplus.     

Robustness of equilibria in anonymous local games

This paper studies the robustness of symmetric equilibria in anonymous local games to perturbations of prior beliefs. Two priors are strategically close on a class of games if players receive similar expected payoffs in equilibrium under the priors, for any game in that class. I show that if the structure of payoff interdependencies is sparse in a well-defined sense, the conditions for strategic proximity in anonymous local games are strictly weaker than the conditions for general Bayesian games of Kajii and Morris (1998) [11] when attention is restricted to symmetric equilibria. Hence, by exploiting the properties of anonymous local games, it is possible to obtain stronger robustness results for this class.     

Stationary monetary equilibria with strictly increasing value functions and non-discrete money holdings distributions: An indeterminacy result

In this paper, we present a search model with divisible money in which there exists a continuum of monetary equilibria with strictly increasing continuous value functions and with non-discrete money holdings distributions.     

Robust equilibria under non-common priors

This paper considers the robustness of equilibria to a small amount of incomplete information, where players are allowed to have heterogeneous priors. An equilibrium of a complete information game is robust to incomplete information under non-common priors if for every incomplete information game where each player's prior assigns high probability on the event that the players know at arbitrarily high order that the payoffs are given by the complete information game, there exists a Bayesian Nash equilibrium that generates behavior close to the equilibrium in consideration. It is shown that for generic games, an equilibrium is robust under non-common priors if and only if it is the unique rationalizable action profile. Set-valued concepts are also introduced, and for generic games, a smallest robust set is shown to exist and coincide with the set of a posteriori equilibria.