Mathematical Social Sciences最新文献

A classification is a surjective mapping from a set of objects to a set of categories. A classification aggregation function aggregates every vector of classifications into a single one. We show that every citizen sovereign and independent classification aggregation function is essentially a dictatorship. This impossibility implies an earlier result of Maniquet and Mongin (2016), who show that every unanimous and independent classification aggregation function is a dictatorship. The relationship between the two impossibilities is reminiscent to the relationship between Wilson’s (1972) and Arrow’s (1951) impossibilities in preference aggregation. Moreover, while the Maniquet-Mongin impossibility rests on the existence of at least three categories, we propose an alternative proof technique that covers the case of two categories, except when the number of objects is also two. We also identify all independent and unanimous classification aggregation functions for the case of two categories and two objects.

In this paper, we consider those voting situations in which each voter decides whether he or she approves each candidate. Given a list of such approvals, a “social preference function” picks a ranking of the candidates. We are interested in finding out which social preference functions are non-manipulable. We show that a particular social preference function, referred to as approval ranking, is more decisive than any other social preference functions satisfying completeness, neutrality, anonymity, and non-manipulability. In addition, we show that approval ranking is axiomatized by these four axioms and tie-breakability.

This paper considers an allocation problem with a finite number of objects and unit-demand agents. The main result is a characterization of a class of strategy-proof price mechanisms on a general domain where preferences over pairs of objects and houses are rational, monotonic, and continuous. A mechanism belongs to this class if and only if the price space is restricted in a special way and, given this restriction, that the mechanism selects minimal equilibrium prices.

We incorporate expressive utility into Börgers’ (2004) canonical symmetric model of costly voting. It is shown that, under reasonable conditions, there exist two types of Bayesian Equilibria, those in which voters vote instrumentally and those in which they vote expressively. We show that equilibria in which voting is expressive is characterized by higher turnout and higher welfare. It is also shown that, in contrast to Borgers, when voting is expressive, turnout is too low.

This article aims to demonstrate how a market exposed to a catastrophic event strives to find a balance between adaptation and mitigation policies through R&D strategies. Our analysis reveals that, within our framework, there exists no trade-off between adaptation and mitigation. Rather, the critical relationship exists between adaptation and pollution because adaptation (wealth accumulation) increases the growth rate of the economy, leading to a higher flow pollution due to the scale effect. We also investigate the long-run effects of pollution taxes on growth rates and the influence of the probability of catastrophic events on these outcomes. Our findings suggest that even with a higher likelihood of catastrophe, the economy can elevate its R&D endeavors, provided that the penalty rate stemming from an abrupt event remains sufficiently high and the economy confronts a risk of a doomsday scenario. Additionally, we illustrate that pollution taxes can foster heightened long-term growth, with the positive effects being more pronounced when the probability of catastrophe is elevated, assuming an adequately substantial penalty rate. Finally, we find that pollution growth can be higher with less polluting inputs due to a scale effect, a phenomenon akin to the Jevons-type paradox.

Social norms, the informal rules of society, and relational utility, e.g. utility generated by guilt, are mechanisms by which cooperation and coordination can be facilitated. Here we add relational utility, derived from social norms, to the standard utility functions for several classic games and find that the qualitative outcome of these games can be altered. We find that social dilemmas can be converted into coordination games that exhibit bistability, polymorphic states with non-zero degrees of cooperation can exist at equilibrium, and that intermediate levels of relational utility (i.e. when norms are only moderately enforced) can be optimal in promoting cooperation.

We consider two-stage electoral competitions with strategic voters, investigating the effects of valence (i.e., a candidate’s personal quality) on policy polarization. In our model, two parties compete in a general election, and each party has two office-seeking candidates. Parties first hold a primary election to decide their representative, and then put forward their winning candidate to compete in the general election. Candidates are thus characterized by their promised policy and their valence. Although voters value policies differently, they value valence uniformly. We focus on a competitive regime pure strategy Nash equilibrium where the candidate with the highest valence does not necessarily win the general election. We provide the sufficient conditions under which such an equilibrium exists, as well as a novel comparative static analysis of the valence differences between candidates (or the valence advantage). Our findings demonstrate that changing the valence advantage in general and primary elections can pose differing implications for policy outcomes and policy polarization.

We study a shortlisting model of choice where a decision-maker first applies her inherent rationale and then follows with a sequence of refined rationales that are triggered by inferior alternatives in a menu. Our decision-maker exhausts all the possible paths of sequential filtering. This model captures choice anomalies in multi-attribute choice space where shortlisting seems to be a natural heuristic, and where existing literature comes short.

We propose an ultimatum bargaining model in which the parties experience an envy-based externality that is private information. Our results indicate that there is a threshold for the proposer’s envy which determines whether there will be either a perfectly equitable, certain agreement or an uncertain, inequitable agreement, and that this threshold rises as the distribution of the responder’s envy level improves in a first-order stochastic-dominance sense. In addition, conditionally on the scenario ruling out a perfectly equitable agreement, we show that the proposer’s envy level plays a dual role: (i) it increases the probability of a negotiation breakdown, and (ii) it constitutes a source of bargaining power. Numerical simulations also allow us to explore some properties of the role played by the responder’s envy and by changes in the envy distributions of the two players. Overall, our theoretical results are consistent with the main evidence from ultimatum experiments conducted in behavioral and neuroscience settings. In addition, we provide testable implications of our model for future experiments.

Electoral volatility measures the degree of vote switching between political parties in two consecutive elections. Political scientists use this as an indicator of party system (in)stability. Pedersen (1979) states that volatility should increase when the number of parties changes and/or relevant parties experience vote transfer between elections. However, his proposed functional form of measuring volatility does not always respond to these changes. To address these limitations, we introduce a class of additively separable electoral volatility measures which are responsive to changes in both the number of parties and their vote shares. We present a set of axioms that are both necessary and sufficient to characterize the proposed class of indices, making the structure of the indices more transparent. The paper also introduces two quasi orders which can rank party systems in terms of all electoral volatility indices satisfying certain intuitively reasonable axioms. Finally, applications of the proposed class of indices and the quasi orders are provided using data from Indian state elections.