Voluntary Participation in a Mechanism Implementing a Public Project

In this study, a participation game in a mechanism to implement a public project is considered; in this game, agents decide simultaneously whether they will participate in the mechanism or not. We characterize the sets of participants at strict Nash equilibria, strong equilibria, and coalition-proof equilibria of the participation game. The three sets of equilibria are shown to coincide and exist. All the equilibrium allocations are Pareto efficient at any one of three notions of equilibria. However, if the public good can be provided in multiple units or if there are multiple projects, then these sets may fail to coincide.Participation game, Public project, Strong equilibrium, Coalition-proof equilibrium, Multi-unit public good, Multiple projects

What factors determine the number of trading partners?

The purpose of the paper is to provide a simple model explaining buyer-supplier relationships and show what factors determine the number of trading partners. We show that when the supplier is able to determine the number of trading partners, the optimal number is small if the supplier's bargaining power with them is weak, the economy of scope in the supplier's variable costs is significant, and that in its sunk investment is weak. Investment may be greater when the number of trading partners is small. The results may be consistent with the formation of Japanese buyer-supplier relations.

Coalition-proofness and dominance relations

We show that, if a game satisfies the conditions of anonymity, monotone externality, and strategic substitutability, then the set of coalition-proof Nash equilibria under strict domination contains that under weak domination.ArticleEconomics Letters. 89(2):174-179 (2005)journal articl

Pre-negotiation commitment and internalization in public good provision through bilateral negotiations

September 2015. Revised August 2017

Coalitional equilibria in non-cooperative games with strategic substitutes : Self-enforcing coalition deviations and irreversibility

Introducing a coalitional equilibrium with restricted deviations, we examine how effectively equilibria based on coalitional stability refine Nash equilibria in games with σ-strategic substitutes and σ-monotone externalities. From the existing equilibria such as coalition-proof Nash equilibria and near-strong Nash equilibria, we can consider several ways to restrict coalitional deviations. We incorporate two natural self-enforcing conditions of coalition deviations, Nash stability and irreversibility, into the coalitional equilibrium and provide a more general analysis than earlier studies. We find it impossible that in each of the two stability concepts, the coalitional equilibrium effectively refines the Nash equilibrium for all games with σ-strategic substitutes and σ-monotone externalities

Coalition-proof Nash equilibria and weakly dominated strategies in aggregative games with strategic substitutes : A note

We examine the relation between coalition-proof Nash equilibrium (Bernheim et al., 1987) and weakly dominated strategies in games with strategic substitutes (SS) and monotone externalities (ME). We show that in σ-interactive games with SS and ME, every coalition-proof Nash equilibrium is a Nash equilibrium with undominated strategies. We also find as a by-product that the set of Nash equilibria coincides with the set of undominated Nash equilibria in those games. The relation between the coalition-proof Nash equilibrium and weakly dominated strategies in games with SS is completely different from that in games with strategic complements

Undertaking nonharmful or harmful public projects through unit-by-unit contribution : Coordination and Pareto efficiency

We examine in detail the implementation of a project that is nonharmful for all agents as well as a project that is harmful for some agents through a unit-by-unit contribution mechanism. For a project that is nonharmful for all agents, effient implementation is supported at one regular Nash equilibrium and several refined Nash equilibria that are stable against coalition deviations. In this sense, this mechanism works well. On the other hand, when the project is harmful for some agents, this mechanism may not have a Nash equilibrium with effient implementation of the project. Even when such a Nash equilibrium exists, it may not be selected by any of the refned Nash equilibria. Thus, in this case, this mechanism does not work. Our result shows that the merit of the unit-by-unit contribution mechanism reported in the literature is partially extensible to the implementation of a public project

Undertaking nonharmful or harmful public projects through unit-by-unit contribution : Coordination and Pareto efficiency

We examine in detail the implementation of a project that is nonharmful for all agents as well as a project that is harmful for some agents through a unit-by-unit contribution mechanism. For a project that is nonharmful for all agents, efficient implementation is supported at one regular Nash equilibrium and several refined Nash equilibria that are stable against coalition deviations. In this sense, this mechanism works well. On the other hand, when the project is harmful for some agents, this mechanism may not have a Nash equilibrium with efficient implementation of the project. Even when such a Nash equilibrium exists, it may not be selected by any of the refined Nash equilibria. Thus, in this case, this mechanism does not work. Our result shows that the merit of the unit-by-unit contribution mechanism reported in the literature is partially extensible to the implementation of a public project