Hideo Konishi - Academia.edu (original) (raw)
Papers by Hideo Konishi
International Journal of Game Theory
This paper introduces a bottleneck game with finite sets of commuters and departing time slots as... more This paper introduces a bottleneck game with finite sets of commuters and departing time slots as an extension of congestion games of Konishi et al. (J Econ Theory 72:225–237, 1997a). After characterizing Nash equilibrium of the game, we provide sufficient conditions for which the equivalence between Nash and strong equilibria holds. Somewhat surprisingly, unlike in congestion games, a Nash equilibrium in pure strategies may often fail to exist, even when players are homogeneous. In contrast, when there is a continuum of atomless players, the existence of a Nash equilibrium and the equivalence between the set of Nash and strong equilibria hold as in congestion games (Konishi et al. 1997a).
Dynamic Games and Applications
We consider a one-to-one assortative matching problem in which matched pairs compete for a prize.... more We consider a one-to-one assortative matching problem in which matched pairs compete for a prize. With such externalities, the standard solution concept, pairwise stable matching, may not exist. In this paper, we consider farsighted agents and analyze the largest consistent set (LCS) of Chwe (1994). Despite the assortative structure of the problem, LCS tend to be large with the standard e¤ectiveness functions: LCS can be the set of all matchings, including an empty matching with no matched pair. By modifying the e¤ectiveness function motivated by Knuth (1976), LCS becomes a singleton of the positive assortative matching. Our results suggest that the choice of e¤ectiveness function can signi…cantly impact the solution in a matching problem with externalities.
The Economic studies quarterly, 1993
SSRN Electronic Journal, 2013
In many industries, …rms reward their customers for making referrals. We analyze a monopoly's opt... more In many industries, …rms reward their customers for making referrals. We analyze a monopoly's optimal policy mix of price, advertising intensity, and referral fee when buyers choose to what extent to refer other consumers to the …rm. When the referral fee can be optimally set by the …rm, it will charge the standard monopoly price. The …rm always advertises less when it uses referrals. We extend the analysis to the case where consumers can target their referrals. In particular, we show that referral targeting could be detrimental for consumers in a low-valuation group.
Social Choice and Welfare, 2006
In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the ... more In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the real-life entry-level labor markets for young physicians who seek residencies at hospitals. In a hospital-intern market, the matching is determined by a centralized clearinghouse using the preferences revealed by interns and hospitals and the number of vacant positions revealed by hospitals. We consider a model in which preferences of hospitals and interns are common knowledge. Hospitals play a capacity-reporting game. We analyze the equilibria of the game-form under the two most widely used matching rules: hospital-optimal and intern-optimal stable rules. We show that (i) there may not be a pure strategy equilibrium in general; and (ii) when a pure strategy equilibrium exists, every hospital weakly prefers this equilibrium outcome to the outcome of any larger capacity proÞle. Finally, we present conditions on preferences to guarantee the existence of pure strategy equilibria. JEL ClassiÞcation Numbers: C72, C78, I11, J44 * We would like to thank Alvin Roth, Tayfun Sönmez, an associate editor and three anonymous referees of the journal for their helpful comments and suggestions which signiÞcantly improved the paper.
Games and Economic Behavior, 2012
This paper considers a resource allocation mechanism that utilizes a pro…t-maximizing auctioneer/... more This paper considers a resource allocation mechanism that utilizes a pro…t-maximizing auctioneer/matchmaker in the Kelso-Crawford (1982) (many-to-one) assignment problem. We consider general and simple (individualized price) message spaces for …rms'reports following Milgrom (2010). We show that in the simple message space, (i) the matchmaker's pro…t is always zero and an acceptable assignment is achieved in every Nash equilibrium, and (ii) the sets of stable assignments and coalitionproof Nash equilibria are equivalent. By contrast, in the general message space, the matchmaker may make a positive pro…t in a Nash equilibrium. This shows that restricting message space not only reduces the information requirement but also improves resource allocation.
Economic Theory, 1997
Summary. This paper establishes an existence theorem of a non-trivial (positive capital stock) st... more Summary. This paper establishes an existence theorem of a non-trivial (positive capital stock) steady–state equilibrium in Diamond’s (1965) overlapping-generations model with production by employing the steady–state consumption curve introduced in Ihori (1978). The assumptions on preferences and production technologies that ensure the existence of a nontrivial steady–state equilibrium are separated from each other, unlike in Galor and Ryder (1989). We also provide two simple examples which illustrate the importance of two conditions in the theorem.
Journal of International Economics, 1999
Using Bernheim and Whinston (1986) common agency game, we endogenize trade policy in a duopoly co... more Using Bernheim and Whinston (1986) common agency game, we endogenize trade policy in a duopoly composed of a domestic firm and a foreign firm, where both firms influence the domestic government's trade policy via their contributions. The foreign firm can jump over trade restrictions by undertaking foreign direct investment (FDI) in the domestic market. The government prefers a voluntary export
Transportation Science, 2004
This paper discusses the uniqueness of user equilibrium in transportation networks with heterogen... more This paper discusses the uniqueness of user equilibrium in transportation networks with heterogeneous commuters. Daganzo (1983) proved the uniqueness of (stochastic) user equilibrium when commuters have heterogeneous tastes over possible paths, but identical disutility functions from time costs. We first show, by example, that his result may not apply in general networks if disutility functions are allowed to differ. However, for “simple” transportation networks, we show that user equilibrium is always unique and weakly Pareto efficient (cf. the Braess example) for a general class of utility functions. We investigate whether this result applies to more general networks. We also show that user equilibrium is unique in a dynamic bottleneck model with a simple network. We discuss an interesting relationship between the following two problems: the existence of user equilibrium in a finite model and the uniqueness of user equilibrium in a continuum model. In the appendix, we also provide...
This paper presents one-to-one matching and assignment problems with externalities across pairs s... more This paper presents one-to-one matching and assignment problems with externalities across pairs such as pairs gure skating competition and joint ventures in oligopolistic markets. In these models, players care not only about their partners but also which and how many rival pairs are formed. Thus, it is important for a deviating pair to know which matching will realize after it deviates from a matching (an e¤ectiveness function) in order to de ne pairwise stable matching. Using a natural e¤ectiveness function for such environments, we show that the assortative matching is pairwise stable. We discuss two generalizations of our model including intrinsic preferences on partners and pair-speci c match qualities to see how our stability concept performs in these generalized models. Keywords: one-to-one matching, matching with externalities, pairwise stable matching, coalition formation, group contest, joint ventures, myopia, farsightedness. JEL Classi cation Numbers: C7, D71, D72. We tha...
All countries would agree to immediate global free trade if countries were compensated for any te... more All countries would agree to immediate global free trade if countries were compensated for any terms-of-trade losses with transfers from countries whose terms-of-trade improve, and if customs unions were required to have no effects on non-member countries. Global free trade with transfers is in the core of a Kemp-Wan-Grinols customs union game. (52 words) 2 1
This note shows that if commodities are tradable across jurisdictions, then it may be efficient t... more This note shows that if commodities are tradable across jurisdictions, then it may be efficient to have heterogeneously sized jurisdictions, even if (i) consumers are identical, (ii) there is one private good and one public good, (iii) utility and production functions are not affected by population (within the relevant range of sizes of jurisdictions).
We consider competitive markets for multiple commodities with endogenous formation of one- or two... more We consider competitive markets for multiple commodities with endogenous formation of one- or two-person households. Within each two-person household, externalities from the partner’s commodity consumption and unpriced actions are allowed. Each individual has two types of traits: observable characteristics and unobservable taste characteristics. Each individual gets utility from his/her own private consumption, from discrete actions such as job-choice, from the partner’s observable characteristics such as appearance and hobbies, from some of the partner’s consumption vectors, and from the partner’s action choices. We investigate competitive market outcomes with an endogenous household structure in which no individual and no man/womanpair can deviate profitably. We find a set of sufficient conditions under which a stable matching equilibrium exists. We further establish the first welfare theorem for this economy.
In this paper, we investigate the effects of a free trade agreement (FTA) with environmental stan... more In this paper, we investigate the effects of a free trade agreement (FTA) with environmental standards between Northern and Southern countries, with explicit considerations for transferring clean technology and enforcing reduced emissions. Southern producers benefit greatly by having access to a Northern market without barriers, while they are reluctant to use new high-cost, clean technology provided by the North. Thus, environmentally conscious Northern countries should design an FTA where Southern countries provide sufficient benefits for the membership while imposing tighter enforcement requirements. Since including too many Southern countries dilutes the benefits of being a member of the FTA, it is in the best interest of the North to limit the number of Southern memberships while requiring strict enforcement of emissions reduction. This may result in unequal treatment among the Southern countries. We provide a quantitative evaluation of FTA policies by using a numerical example.
Keio economic studies, 1999
Although protectionism became a salient issue in the 2016 presidential election campaign, both Re... more Although protectionism became a salient issue in the 2016 presidential election campaign, both Republican and Democratic adminis- trations have been silently promoting free trade for decades. We set up a two-party electoral competition model in a two-dimensional policy space with campaign contributions by a group (exporting/multinational firms) that is interested in promoting free trade, for which voters do not have positive sentiment. Assuming that voters are impressionable to campaign spending for/against candidates, we analyze the optimal contract between the interest group and the candidates on policy is- sues and campaign contributions. If voters' negative sentiment to free trade is not too strong, the interest group tends to contribute to both candidates to make free trade a nonsalient issue, and the candidates compete over the other (ideological) dimension only. If votersineg- ative sentiment to free trade is strong, the interest group tends to contribute to a more mallea...
This paper introduces a bottleneck game with finite sets of commuters and departing time slots as... more This paper introduces a bottleneck game with finite sets of commuters and departing time slots as an extension of congestion games by Milchtaich (1996). After characterizing Nash equilibrium of the game, we provide sufficient conditions for which the equivalence between Nash and strong equilibria holds. Somewhat surprisingly, unlike in congestion games, a Nash equilibrium in pure strategies may often fail to exist, even when players are homogeneous. In contrast, when there is a continuum of atomless players, the existence of a Nash equilibrium and the equivalence between the set of Nash and strong equilibria hold as in congestion games (Konishi, Le Breton, and Weber, 1997a).
We consider games in which team leaders strategically choose the order of players sent to the bat... more We consider games in which team leaders strategically choose the order of players sent to the battle eld in majoritarian team contests with multiple pairwise battles as in Fu, Lu, and Pan (2015 American Economic Review). We consider one-shot orderchoice games and battle-by-battle sequential player choice games. We show that as long as the number of players on each team is the same as the number of battles, the equilibrium winning probability of a team and the ex ante expected e¤ort of each player in a multi-battle contest are independent of whether playersassignments are one-shot or battle-by-battle sequential. This equilibrium winning probability and ex ante expected total e¤ort coincide with those where the player matching is chosen totally randomly with an equal probability lottery by the contest organizer. Finally, we show how player choices add subtleties to the equivalence result by examples. We thank Stefano Barbieri, Qiang Fu, and Jingfeng Lu for their helpful comments and ...
In this paper we propose a tractable model of partisan gerrymandering followed by electoral compe... more In this paper we propose a tractable model of partisan gerrymandering followed by electoral competitions in policy positions and transfer promises in multiple districts. With such pork-barrel considerations, we generally nd that gerrymandering results in (i) packing the opponent partys supporters in losing districts, and (ii) more extreme policies in winning districts. However, depending on the party leadersand voterspreference intensity for policy positions, and depending on how much freedom the leader has in redistricting, we obtain a variety of optimal gerrymandering policies. The well-known packand-crack gerrymandering is not necessarily optimal: the party leader may choose to create some extremely polarized districts to avoid making costly pork-barrel promises, even with candidates who have more polarized positions than hers. Keywords: electoral competition, gerrymandering, policy convergence/divergence, pork-barrel politics JEL Classi cation Numbers: C72, D72 Still prelimi...
Social Choice and Welfare
In this paper, we consider a prize-sharing rule design problem in a group contest with effort com... more In this paper, we consider a prize-sharing rule design problem in a group contest with effort complementarities within groups by employing a CES effort aggregator function. We derive the conditions for a monopolization rule that dominates an egalitarian rule if the objective of the rule design is to maximize the group's winning probability. We find conditions under which the monopolization rule maximizes the group's winning probability, while the egalitarian rule is strictly preferred by all members of the group. Without effort complementarity, there cannot be such a conflict of interest.
International Journal of Game Theory
This paper introduces a bottleneck game with finite sets of commuters and departing time slots as... more This paper introduces a bottleneck game with finite sets of commuters and departing time slots as an extension of congestion games of Konishi et al. (J Econ Theory 72:225–237, 1997a). After characterizing Nash equilibrium of the game, we provide sufficient conditions for which the equivalence between Nash and strong equilibria holds. Somewhat surprisingly, unlike in congestion games, a Nash equilibrium in pure strategies may often fail to exist, even when players are homogeneous. In contrast, when there is a continuum of atomless players, the existence of a Nash equilibrium and the equivalence between the set of Nash and strong equilibria hold as in congestion games (Konishi et al. 1997a).
Dynamic Games and Applications
We consider a one-to-one assortative matching problem in which matched pairs compete for a prize.... more We consider a one-to-one assortative matching problem in which matched pairs compete for a prize. With such externalities, the standard solution concept, pairwise stable matching, may not exist. In this paper, we consider farsighted agents and analyze the largest consistent set (LCS) of Chwe (1994). Despite the assortative structure of the problem, LCS tend to be large with the standard e¤ectiveness functions: LCS can be the set of all matchings, including an empty matching with no matched pair. By modifying the e¤ectiveness function motivated by Knuth (1976), LCS becomes a singleton of the positive assortative matching. Our results suggest that the choice of e¤ectiveness function can signi…cantly impact the solution in a matching problem with externalities.
The Economic studies quarterly, 1993
SSRN Electronic Journal, 2013
In many industries, …rms reward their customers for making referrals. We analyze a monopoly's opt... more In many industries, …rms reward their customers for making referrals. We analyze a monopoly's optimal policy mix of price, advertising intensity, and referral fee when buyers choose to what extent to refer other consumers to the …rm. When the referral fee can be optimally set by the …rm, it will charge the standard monopoly price. The …rm always advertises less when it uses referrals. We extend the analysis to the case where consumers can target their referrals. In particular, we show that referral targeting could be detrimental for consumers in a low-valuation group.
Social Choice and Welfare, 2006
In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the ... more In this paper, we analyze capacity manipulation games in hospital-intern markets inspired by the real-life entry-level labor markets for young physicians who seek residencies at hospitals. In a hospital-intern market, the matching is determined by a centralized clearinghouse using the preferences revealed by interns and hospitals and the number of vacant positions revealed by hospitals. We consider a model in which preferences of hospitals and interns are common knowledge. Hospitals play a capacity-reporting game. We analyze the equilibria of the game-form under the two most widely used matching rules: hospital-optimal and intern-optimal stable rules. We show that (i) there may not be a pure strategy equilibrium in general; and (ii) when a pure strategy equilibrium exists, every hospital weakly prefers this equilibrium outcome to the outcome of any larger capacity proÞle. Finally, we present conditions on preferences to guarantee the existence of pure strategy equilibria. JEL ClassiÞcation Numbers: C72, C78, I11, J44 * We would like to thank Alvin Roth, Tayfun Sönmez, an associate editor and three anonymous referees of the journal for their helpful comments and suggestions which signiÞcantly improved the paper.
Games and Economic Behavior, 2012
This paper considers a resource allocation mechanism that utilizes a pro…t-maximizing auctioneer/... more This paper considers a resource allocation mechanism that utilizes a pro…t-maximizing auctioneer/matchmaker in the Kelso-Crawford (1982) (many-to-one) assignment problem. We consider general and simple (individualized price) message spaces for …rms'reports following Milgrom (2010). We show that in the simple message space, (i) the matchmaker's pro…t is always zero and an acceptable assignment is achieved in every Nash equilibrium, and (ii) the sets of stable assignments and coalitionproof Nash equilibria are equivalent. By contrast, in the general message space, the matchmaker may make a positive pro…t in a Nash equilibrium. This shows that restricting message space not only reduces the information requirement but also improves resource allocation.
Economic Theory, 1997
Summary. This paper establishes an existence theorem of a non-trivial (positive capital stock) st... more Summary. This paper establishes an existence theorem of a non-trivial (positive capital stock) steady–state equilibrium in Diamond’s (1965) overlapping-generations model with production by employing the steady–state consumption curve introduced in Ihori (1978). The assumptions on preferences and production technologies that ensure the existence of a nontrivial steady–state equilibrium are separated from each other, unlike in Galor and Ryder (1989). We also provide two simple examples which illustrate the importance of two conditions in the theorem.
Journal of International Economics, 1999
Using Bernheim and Whinston (1986) common agency game, we endogenize trade policy in a duopoly co... more Using Bernheim and Whinston (1986) common agency game, we endogenize trade policy in a duopoly composed of a domestic firm and a foreign firm, where both firms influence the domestic government's trade policy via their contributions. The foreign firm can jump over trade restrictions by undertaking foreign direct investment (FDI) in the domestic market. The government prefers a voluntary export
Transportation Science, 2004
This paper discusses the uniqueness of user equilibrium in transportation networks with heterogen... more This paper discusses the uniqueness of user equilibrium in transportation networks with heterogeneous commuters. Daganzo (1983) proved the uniqueness of (stochastic) user equilibrium when commuters have heterogeneous tastes over possible paths, but identical disutility functions from time costs. We first show, by example, that his result may not apply in general networks if disutility functions are allowed to differ. However, for “simple” transportation networks, we show that user equilibrium is always unique and weakly Pareto efficient (cf. the Braess example) for a general class of utility functions. We investigate whether this result applies to more general networks. We also show that user equilibrium is unique in a dynamic bottleneck model with a simple network. We discuss an interesting relationship between the following two problems: the existence of user equilibrium in a finite model and the uniqueness of user equilibrium in a continuum model. In the appendix, we also provide...
This paper presents one-to-one matching and assignment problems with externalities across pairs s... more This paper presents one-to-one matching and assignment problems with externalities across pairs such as pairs gure skating competition and joint ventures in oligopolistic markets. In these models, players care not only about their partners but also which and how many rival pairs are formed. Thus, it is important for a deviating pair to know which matching will realize after it deviates from a matching (an e¤ectiveness function) in order to de ne pairwise stable matching. Using a natural e¤ectiveness function for such environments, we show that the assortative matching is pairwise stable. We discuss two generalizations of our model including intrinsic preferences on partners and pair-speci c match qualities to see how our stability concept performs in these generalized models. Keywords: one-to-one matching, matching with externalities, pairwise stable matching, coalition formation, group contest, joint ventures, myopia, farsightedness. JEL Classi cation Numbers: C7, D71, D72. We tha...
All countries would agree to immediate global free trade if countries were compensated for any te... more All countries would agree to immediate global free trade if countries were compensated for any terms-of-trade losses with transfers from countries whose terms-of-trade improve, and if customs unions were required to have no effects on non-member countries. Global free trade with transfers is in the core of a Kemp-Wan-Grinols customs union game. (52 words) 2 1
This note shows that if commodities are tradable across jurisdictions, then it may be efficient t... more This note shows that if commodities are tradable across jurisdictions, then it may be efficient to have heterogeneously sized jurisdictions, even if (i) consumers are identical, (ii) there is one private good and one public good, (iii) utility and production functions are not affected by population (within the relevant range of sizes of jurisdictions).
We consider competitive markets for multiple commodities with endogenous formation of one- or two... more We consider competitive markets for multiple commodities with endogenous formation of one- or two-person households. Within each two-person household, externalities from the partner’s commodity consumption and unpriced actions are allowed. Each individual has two types of traits: observable characteristics and unobservable taste characteristics. Each individual gets utility from his/her own private consumption, from discrete actions such as job-choice, from the partner’s observable characteristics such as appearance and hobbies, from some of the partner’s consumption vectors, and from the partner’s action choices. We investigate competitive market outcomes with an endogenous household structure in which no individual and no man/womanpair can deviate profitably. We find a set of sufficient conditions under which a stable matching equilibrium exists. We further establish the first welfare theorem for this economy.
In this paper, we investigate the effects of a free trade agreement (FTA) with environmental stan... more In this paper, we investigate the effects of a free trade agreement (FTA) with environmental standards between Northern and Southern countries, with explicit considerations for transferring clean technology and enforcing reduced emissions. Southern producers benefit greatly by having access to a Northern market without barriers, while they are reluctant to use new high-cost, clean technology provided by the North. Thus, environmentally conscious Northern countries should design an FTA where Southern countries provide sufficient benefits for the membership while imposing tighter enforcement requirements. Since including too many Southern countries dilutes the benefits of being a member of the FTA, it is in the best interest of the North to limit the number of Southern memberships while requiring strict enforcement of emissions reduction. This may result in unequal treatment among the Southern countries. We provide a quantitative evaluation of FTA policies by using a numerical example.
Keio economic studies, 1999
Although protectionism became a salient issue in the 2016 presidential election campaign, both Re... more Although protectionism became a salient issue in the 2016 presidential election campaign, both Republican and Democratic adminis- trations have been silently promoting free trade for decades. We set up a two-party electoral competition model in a two-dimensional policy space with campaign contributions by a group (exporting/multinational firms) that is interested in promoting free trade, for which voters do not have positive sentiment. Assuming that voters are impressionable to campaign spending for/against candidates, we analyze the optimal contract between the interest group and the candidates on policy is- sues and campaign contributions. If voters' negative sentiment to free trade is not too strong, the interest group tends to contribute to both candidates to make free trade a nonsalient issue, and the candidates compete over the other (ideological) dimension only. If votersineg- ative sentiment to free trade is strong, the interest group tends to contribute to a more mallea...
This paper introduces a bottleneck game with finite sets of commuters and departing time slots as... more This paper introduces a bottleneck game with finite sets of commuters and departing time slots as an extension of congestion games by Milchtaich (1996). After characterizing Nash equilibrium of the game, we provide sufficient conditions for which the equivalence between Nash and strong equilibria holds. Somewhat surprisingly, unlike in congestion games, a Nash equilibrium in pure strategies may often fail to exist, even when players are homogeneous. In contrast, when there is a continuum of atomless players, the existence of a Nash equilibrium and the equivalence between the set of Nash and strong equilibria hold as in congestion games (Konishi, Le Breton, and Weber, 1997a).
We consider games in which team leaders strategically choose the order of players sent to the bat... more We consider games in which team leaders strategically choose the order of players sent to the battle eld in majoritarian team contests with multiple pairwise battles as in Fu, Lu, and Pan (2015 American Economic Review). We consider one-shot orderchoice games and battle-by-battle sequential player choice games. We show that as long as the number of players on each team is the same as the number of battles, the equilibrium winning probability of a team and the ex ante expected e¤ort of each player in a multi-battle contest are independent of whether playersassignments are one-shot or battle-by-battle sequential. This equilibrium winning probability and ex ante expected total e¤ort coincide with those where the player matching is chosen totally randomly with an equal probability lottery by the contest organizer. Finally, we show how player choices add subtleties to the equivalence result by examples. We thank Stefano Barbieri, Qiang Fu, and Jingfeng Lu for their helpful comments and ...
In this paper we propose a tractable model of partisan gerrymandering followed by electoral compe... more In this paper we propose a tractable model of partisan gerrymandering followed by electoral competitions in policy positions and transfer promises in multiple districts. With such pork-barrel considerations, we generally nd that gerrymandering results in (i) packing the opponent partys supporters in losing districts, and (ii) more extreme policies in winning districts. However, depending on the party leadersand voterspreference intensity for policy positions, and depending on how much freedom the leader has in redistricting, we obtain a variety of optimal gerrymandering policies. The well-known packand-crack gerrymandering is not necessarily optimal: the party leader may choose to create some extremely polarized districts to avoid making costly pork-barrel promises, even with candidates who have more polarized positions than hers. Keywords: electoral competition, gerrymandering, policy convergence/divergence, pork-barrel politics JEL Classi cation Numbers: C72, D72 Still prelimi...
Social Choice and Welfare
In this paper, we consider a prize-sharing rule design problem in a group contest with effort com... more In this paper, we consider a prize-sharing rule design problem in a group contest with effort complementarities within groups by employing a CES effort aggregator function. We derive the conditions for a monopolization rule that dominates an egalitarian rule if the objective of the rule design is to maximize the group's winning probability. We find conditions under which the monopolization rule maximizes the group's winning probability, while the egalitarian rule is strictly preferred by all members of the group. Without effort complementarity, there cannot be such a conflict of interest.