On the General Existence of Pure Strategy Political Competition Equilibrium in Multi-dimensional Party-Faction Models

In this paper, we consider political competition games of two parties in multi-dimensional policy spaces, where the two parties have two factions, opportunists and militants, that intra-party bargain with each other. In such a game, we adopt the party-unanimity Nash equilibrium (PUNE) [Roemer (1998; 1999; 2001)] as an appropriate solution concept, and examine the general existence problem of this. In particular, we suppose that any faction of each party does not necessarily have dictatorial power. We then provide a general existence theorem for PUNE in this class of games.multi-dimensional political competition games, partyunanimity Nash equilibria, pure-compromise PUNE

On Non-welfarist Social Ordering Functions

In this paper, criticizing the welfarist's framework in traditional welfare economics which provides a rather limited perspective for social evaluation, we propose a more comprehensive framework in which extended social ordering functions (ESOFs) are introduced. In this framework, not only welfaristic values, but also non-welfaristic values can be treated appropriately. Then, we examine the possibility of non-welfarist ESOFs which meet a value of Individual Autonomy, a criterion of non-welfairst distributive justice, and the welfarist Pareto principle. First, there is no first best ESOF in the sense that the above three axioms are satisfied simultaneously. Second, however, we can show the existence of some second best ESOFs, using a weaker lexicographic application method.

Class and Exploitation in General Convex Cone Economies

In this paper, we examine what appropriate formulations for labor exploitation are, in order to explain the emergence of class and exploitation status in capitalist economies. Given the well-known controversy on plausible formulations for labor exploitation in joint production economies, we propose an axiom, Axiom for Labor Exploitation (LE), which every formulation of labor exploitation should satisfy to be considered 'Marxian.' Using this axiom, the necessary and sufficient condition for plausible formulations of Marxian exploitation is characterized to verify Class-Exploitation Correspondence Principle (CECP) [Roemer (1982)]. According to this, if some labor exploitation formulations, such as the well-known formulations of Morishima (1974) and Roemer (1982; Chapter 5) are applied, CECP no longer holds in general convex cone economies. Based upon this argument, we propose two new definitions of labor exploitation, each of which verifies CECP as well as Fundamental Marxian Theorem (FMT).convex cone economies, reproducible solutions, FundamentalMarxian Theorem, Class-Exploitation Correspondence Principle, Axiom for Labor Exploitation

Partially-honest Nash implementation: Characterization results

This paper studies implementation problems in the wake of a recent new trend of implementation theory which incorporates a non-consequentialist flavor of the evidence from experimental and behavioral economics into the issues. Specifically, following the seminal works by Matsushima (2008) and Dutta and Sen (2009), the paper considers implementation problems with partially honest agents, which presume that there exists at least one individual in the society who concerns herself with not only outcomes but also honest behavior at least in a limited manner. Given this setting, the paper provides a general characterization of Nash implementation with partially-honest individuals. It also provides the necessary and sufficient condition for Nash implementation with partially-honest individuals by mechanisms with some types of strategy-space reductions. As a consequence, it shows that, in contrast to the case of the standard framework, the equivalence between Nash implementation and Nash implementation with strategy space reduction no longer holds.

Natural implementation with partially honest agents in economic environments

In this paper, we introduce the weak and the strong notions of partially honest agents (Dutta and Sen, 2012), and then study implementation by natural price-quantity mechanisms (Saijo et al., 1996, 1999) in pure exchange economies with three or more agents in which pure-consequentialistically rational agents and partially honest agents coexist. Firstly, assuming that there exists at least one partially honest agent in either the weak notion or the strong notion, the class of efficient social choice correspondences which are Nash-implementable by such mechanisms is characterized. Secondly, the (unconstrained) Walrasian correspondence is shown to be implementable by such a mechanism when there is at least one partially honest agent of the strong type, which may provide a behavioral foundation for decentralized implementation of the Walrasian equilibrium. Finally, in this set-up, the effects of honesty on the implementation of more equitable Pareto optimal allocations can be viewed as negligible.

Rationality and the Nash Solution to Non-convex Bargaining Problems

Conditions α and β are two well-known rationality conditions in the theory of rational choice. This paper examines the implication of weaker versions of these two rationality conditions in the context of solutions to non-convex bargaining problems. It is shown that, together with the standard axioms of efficiency, anonymity and scale invariance, they characterize the Nash solution. This result makes a further connection between solutions to non-convex bargaining problems and rationalizability of choice functions in the theory of rational choice.

Alternative Characterizations of the Proportional Solution for Nonconvex Bargaining Problems with Claims

We provide three alternative characterizations of the proportional solution defined on compact and comprehensive bargaining problems with claims that are not necessarily convex. One characterization result is obtained by using, together with other standard axioms, two solidarity axioms. Another characterization theorem shows that the single-valuedness axiom is dispensable even within the class of nonconvex problems if the standard symmetry axiom is imposed.Bargaining problems, Claims point, Proportional solution, Nonconvexity, Solidarity axioms

A New Insight into Three Bargaining Solutions in Convex Problems

We reconsider the three well-known solutions: the Nash, the egalitarian and the Kalai-Smorodinsky solutions, to the classical domains of convex bargaining problems. A new proof for the Nash solution that highlights the crucial role the axiom Contraction Independence plays is provided. We also give new axiomatic characterizations for both the egalitarian and the Kalai-Smorodinsky solutions. Our results focus on both contraction and expansion independence properties of bargaining problems and, as a consequence, some new insights on the three solutions from the perspective of rational choice may be derived.

Proportional Nash solutions - A new and procedural analysis of nonconvex bargaining problems

This paper studies the Nash solution to nonconvex bargaining problems. The Nash solution in such a context is typically multi-valued. We introduce a procedure to exclude some options recommended by the Nash solution. The procedure is based on the idea of the Kalai-Smorodinsky solution which has the same informational requirement on individual utilities as the Nash solution does and has an equity consideration as well. We then use this procedure to introduce two new solutions to nonconvex bargaining problems and study them axiomatically.