Ezra Einy - Academia.edu (original) (raw)

Papers by Ezra Einy

Research paper thumbnail of Information Advantage and Dominant Strategies in Second-Price Auctions

RePEc: Research Papers in Economics, Nov 1, 2000

We study a general model of common-value second-price auctions with differential information. We ... more We study a general model of common-value second-price auctions with differential information. We show that one of the bidders has an information advantage over the other bidders if and only if he possesses a dominant strategy. A dominant strategy is, in fact, unique, and is given by the conditional expectation of the common value with respect to his information field. Furthermore, when a bidder has information advantage, other bidders cannot make a profit.

Research paper thumbnail of Equilibrium existence in Tullock contests with incomplete information

Journal of Mathematical Economics, 2015

We show that under general assumptions a Tullock contest in which the information endowment of ea... more We show that under general assumptions a Tullock contest in which the information endowment of each contender is described by a countable partition has a pure strategy Bayesian Nash equilibrium.

Research paper thumbnail of Pure-strategy equilibrium in Bayesian potential games with absolutely continuous information

Games and Economic Behavior

Research paper thumbnail of Tullock contests reward information advantages

Research paper thumbnail of 2001b): “The bargaining set of a large economy with differential information,” Economic Theory 18

Abstract------------------------------------------------------------We study the Mas-Collel barga... more Abstract------------------------------------------------------------We study the Mas-Collel bargaining set of an exchange economy with differential information and a continuum of traders. We established the equivalence of the private bargaining set and the set of Radner competitive equilibrium allocations. As for the weak fine bargaining set, we show that it contains the set of competitive equilibrium allocations of an associated symmetric information economy in which each trader has the "joint information » of all the traders in the original economy, but unlike the weak fine core and the set of fine value allocations, it may also contain allocations which are not competitive in the associated economy.

Research paper thumbnail of On the Existence of Bayesian Cournot

We show that even in very simple oligopolies with differential information a (Bayesian) Cournot e... more We show that even in very simple oligopolies with differential information a (Bayesian) Cournot equilibrium in pure strategies may not exist, or be unique. However, we find sufficient conditions for existence, and for uniqueness, of Cournot equilibrium in a certain class of industries. More general results arise when negative prices are allowed.

Research paper thumbnail of Compound Voting and the Banzhaf Power Index

Discussion Paper Series, 2003

We present three axioms for a power index defined on the domain of simple (voting) games. Positiv... more We present three axioms for a power index defined on the domain of simple (voting) games. Positivity requires that no voter has negative power, and at least one has positive power. Transfer requires that, when winning coalitions are enhanced in a game, the change in voting power depends only on the change in the game, i.e., on the set of

Research paper thumbnail of Coalition-proof communication equilibria

Research paper thumbnail of Tullock contests with asymmetric information

Under standard assumptions about players'cost functions, we show that a Tullock contest with asym... more Under standard assumptions about players'cost functions, we show that a Tullock contest with asymmetric information has a pure strategy equilibrium. Next we study Tullock contests in which players have a common value and a common state-independent linear cost function. A two-player contest in which one player has an information advantage has a unique equilibrium. In equilibrium both players exert the same expected e¤ort, and although the player with an information advantage wins the prize with probability less than one-half, his payo¤ is greater or equal to that of his opponent. When there are more than two players in the contest, having information advantage leads to higher payo¤s, but the other properties of equilibrium no longer hold.

Research paper thumbnail of The shapley value on some lattices of monotonic games

Mathematical Social Sciences, 1988

... Then auT,(S)=0 or buTZ(S)=0. Therefore ((auT,)n(buTZ)) (S)=0=mina, b)uTUTZ(S). Corollary 12. ... more ... Then auT,(S)=0 or buTZ(S)=0. Therefore ((auT,)n(buTZ)) (S)=0=mina, b)uTUTZ(S). Corollary 12. Let AC (R+ such that 0 e A, and let G be an additive abelian group. Then any valuation f : Fm. ... xn) a IR", we denote rrx= 6 E. Einy The Shaplev value on some lattices (xn(j), ... xn(n ...

Research paper thumbnail of On the Core of an Economy with DiKerential Information

Research paper thumbnail of A non-cooperative interpretation of bargaining sets

Review of Economic Design, 1999

This paper provides a non-cooperative interpretation for bargaining sets concepts in economic env... more This paper provides a non-cooperative interpretation for bargaining sets concepts in economic environments. We investigate the implementability of the Aumann-Maschler and Mas-Colell bargaining sets, and provide mechanisms whose subgame perfect equilibrium outcomes realize these sets. These mechanisms, in contrast to general mechanisms suggested in the implementation literature, have a natural structure closely related to that of the rationale underlying the bargaining sets. Furthermore, the strategy sets consist mainly of allocations and coalitions (thus avoiding any reference to preference parameters) and are finite dimensional.

Research paper thumbnail of Large symmetric games and characterized by completeness of the desirability relation

Research paper thumbnail of The desirability relation of simple games

Mathematical Social Sciences, 1985

Abstract We prove some properties of simple games with a complete desirability relation, and inve... more Abstract We prove some properties of simple games with a complete desirability relation, and investigate the relationships between the desirability of a simple game G and that of some simple games that are derived from G . We also provide an example of a proper simple game that has a complete and acyclic desirability relation but is not a weighted majority game.

Research paper thumbnail of On preference relations which satisfy weak independence property

Journal of Mathematical Economics, 1989

Abstract We prove some representation theorems for two classes of preference relations on a conve... more Abstract We prove some representation theorems for two classes of preference relations on a convex subset of a topological vector space: continuous preferences which satisfy weak independence property with respect to convex combinations, and continuous preferences which are consistent with respect to translations.

Research paper thumbnail of On non-atomic weighted majority games

Journal of Mathematical Economics, 1990

Abstract We present some characterizations for the class of non-atomic weighted majority games wh... more Abstract We present some characterizations for the class of non-atomic weighted majority games which are defined on a measurable space ( I , C ). The characterizations are done within the class of all monotonic simple games which are upper semicontinuous on C and continuous at I with respect to the N A -topology on C . We also use the results on simple games to obtain a characterization for the games of the form ƒ ∘ μ where μ is a non-atomic probability measure and ƒ is a nondecreasing upper semicontinuous function on [0,1].

Research paper thumbnail of Rational expectations equilibria and the ex-post core of an economy with asymmetric information

Journal of Mathematical Economics, 2000

We study the relationship between the set of rational expectations equilibrium allocations and th... more We study the relationship between the set of rational expectations equilibrium allocations and the ex-post core of exchange economies with asymmetric information.

Research paper thumbnail of Dominance solvability of second-price auctions with differential information

Journal of Mathematical Economics, 2002

We study a class of common-value second-price auctions with differential information. This class ... more We study a class of common-value second-price auctions with differential information. This class of common-value auctions is characterized by the property that each player's information set is connected with respect to the common value. We show that the entire class is dominance solvable, and that there is a natural single-valued selection from the resulting set of sophisticated equilibria. Additionally, it is shown that bidder's information advantage over others is rewarded in sophisticated equilibria.

Research paper thumbnail of On the Core of an Economy with Differential Information

Journal of Economic Theory, 2000

We show that the (interim) fine core of an atomless exchange economy with differential informatio... more We show that the (interim) fine core of an atomless exchange economy with differential information is a subset of the ex-post core of the economy. Moreover, the interim fine core may be empty, and therefore it may be a proper subset of the ex-post core. The inclusion relation does not hold for economies with a finite number of traders.

Research paper thumbnail of Linear measures of inequality for cooperative games

Journal of Economic Theory, 1991

We provide a self-contained axiomatization of linear inequality measures for coalitional games. A... more We provide a self-contained axiomatization of linear inequality measures for coalitional games. Adding one axiom to those of Weymark (Math. Sot. Sci. 1 (1981) 4099430), we prove that all such measures must be generalized Gini functions of the Shapley value. Also, we generalize the foregoing result to the spaces pNA(p) of non-atomic games. Journal of Economic Literature Classification Numbers: 024. 026.

Research paper thumbnail of Information Advantage and Dominant Strategies in Second-Price Auctions

RePEc: Research Papers in Economics, Nov 1, 2000

We study a general model of common-value second-price auctions with differential information. We ... more We study a general model of common-value second-price auctions with differential information. We show that one of the bidders has an information advantage over the other bidders if and only if he possesses a dominant strategy. A dominant strategy is, in fact, unique, and is given by the conditional expectation of the common value with respect to his information field. Furthermore, when a bidder has information advantage, other bidders cannot make a profit.

Research paper thumbnail of Equilibrium existence in Tullock contests with incomplete information

Journal of Mathematical Economics, 2015

We show that under general assumptions a Tullock contest in which the information endowment of ea... more We show that under general assumptions a Tullock contest in which the information endowment of each contender is described by a countable partition has a pure strategy Bayesian Nash equilibrium.

Research paper thumbnail of Pure-strategy equilibrium in Bayesian potential games with absolutely continuous information

Games and Economic Behavior

Research paper thumbnail of Tullock contests reward information advantages

Research paper thumbnail of 2001b): “The bargaining set of a large economy with differential information,” Economic Theory 18

Abstract------------------------------------------------------------We study the Mas-Collel barga... more Abstract------------------------------------------------------------We study the Mas-Collel bargaining set of an exchange economy with differential information and a continuum of traders. We established the equivalence of the private bargaining set and the set of Radner competitive equilibrium allocations. As for the weak fine bargaining set, we show that it contains the set of competitive equilibrium allocations of an associated symmetric information economy in which each trader has the "joint information » of all the traders in the original economy, but unlike the weak fine core and the set of fine value allocations, it may also contain allocations which are not competitive in the associated economy.

Research paper thumbnail of On the Existence of Bayesian Cournot

We show that even in very simple oligopolies with differential information a (Bayesian) Cournot e... more We show that even in very simple oligopolies with differential information a (Bayesian) Cournot equilibrium in pure strategies may not exist, or be unique. However, we find sufficient conditions for existence, and for uniqueness, of Cournot equilibrium in a certain class of industries. More general results arise when negative prices are allowed.

Research paper thumbnail of Compound Voting and the Banzhaf Power Index

Discussion Paper Series, 2003

We present three axioms for a power index defined on the domain of simple (voting) games. Positiv... more We present three axioms for a power index defined on the domain of simple (voting) games. Positivity requires that no voter has negative power, and at least one has positive power. Transfer requires that, when winning coalitions are enhanced in a game, the change in voting power depends only on the change in the game, i.e., on the set of

Research paper thumbnail of Coalition-proof communication equilibria

Research paper thumbnail of Tullock contests with asymmetric information

Under standard assumptions about players'cost functions, we show that a Tullock contest with asym... more Under standard assumptions about players'cost functions, we show that a Tullock contest with asymmetric information has a pure strategy equilibrium. Next we study Tullock contests in which players have a common value and a common state-independent linear cost function. A two-player contest in which one player has an information advantage has a unique equilibrium. In equilibrium both players exert the same expected e¤ort, and although the player with an information advantage wins the prize with probability less than one-half, his payo¤ is greater or equal to that of his opponent. When there are more than two players in the contest, having information advantage leads to higher payo¤s, but the other properties of equilibrium no longer hold.

Research paper thumbnail of The shapley value on some lattices of monotonic games

Mathematical Social Sciences, 1988

... Then auT,(S)=0 or buTZ(S)=0. Therefore ((auT,)n(buTZ)) (S)=0=mina, b)uTUTZ(S). Corollary 12. ... more ... Then auT,(S)=0 or buTZ(S)=0. Therefore ((auT,)n(buTZ)) (S)=0=mina, b)uTUTZ(S). Corollary 12. Let AC (R+ such that 0 e A, and let G be an additive abelian group. Then any valuation f : Fm. ... xn) a IR", we denote rrx= 6 E. Einy The Shaplev value on some lattices (xn(j), ... xn(n ...

Research paper thumbnail of On the Core of an Economy with DiKerential Information

Research paper thumbnail of A non-cooperative interpretation of bargaining sets

Review of Economic Design, 1999

This paper provides a non-cooperative interpretation for bargaining sets concepts in economic env... more This paper provides a non-cooperative interpretation for bargaining sets concepts in economic environments. We investigate the implementability of the Aumann-Maschler and Mas-Colell bargaining sets, and provide mechanisms whose subgame perfect equilibrium outcomes realize these sets. These mechanisms, in contrast to general mechanisms suggested in the implementation literature, have a natural structure closely related to that of the rationale underlying the bargaining sets. Furthermore, the strategy sets consist mainly of allocations and coalitions (thus avoiding any reference to preference parameters) and are finite dimensional.

Research paper thumbnail of Large symmetric games and characterized by completeness of the desirability relation

Research paper thumbnail of The desirability relation of simple games

Mathematical Social Sciences, 1985

Abstract We prove some properties of simple games with a complete desirability relation, and inve... more Abstract We prove some properties of simple games with a complete desirability relation, and investigate the relationships between the desirability of a simple game G and that of some simple games that are derived from G . We also provide an example of a proper simple game that has a complete and acyclic desirability relation but is not a weighted majority game.

Research paper thumbnail of On preference relations which satisfy weak independence property

Journal of Mathematical Economics, 1989

Abstract We prove some representation theorems for two classes of preference relations on a conve... more Abstract We prove some representation theorems for two classes of preference relations on a convex subset of a topological vector space: continuous preferences which satisfy weak independence property with respect to convex combinations, and continuous preferences which are consistent with respect to translations.

Research paper thumbnail of On non-atomic weighted majority games

Journal of Mathematical Economics, 1990

Abstract We present some characterizations for the class of non-atomic weighted majority games wh... more Abstract We present some characterizations for the class of non-atomic weighted majority games which are defined on a measurable space ( I , C ). The characterizations are done within the class of all monotonic simple games which are upper semicontinuous on C and continuous at I with respect to the N A -topology on C . We also use the results on simple games to obtain a characterization for the games of the form ƒ ∘ μ where μ is a non-atomic probability measure and ƒ is a nondecreasing upper semicontinuous function on [0,1].

Research paper thumbnail of Rational expectations equilibria and the ex-post core of an economy with asymmetric information

Journal of Mathematical Economics, 2000

We study the relationship between the set of rational expectations equilibrium allocations and th... more We study the relationship between the set of rational expectations equilibrium allocations and the ex-post core of exchange economies with asymmetric information.

Research paper thumbnail of Dominance solvability of second-price auctions with differential information

Journal of Mathematical Economics, 2002

We study a class of common-value second-price auctions with differential information. This class ... more We study a class of common-value second-price auctions with differential information. This class of common-value auctions is characterized by the property that each player's information set is connected with respect to the common value. We show that the entire class is dominance solvable, and that there is a natural single-valued selection from the resulting set of sophisticated equilibria. Additionally, it is shown that bidder's information advantage over others is rewarded in sophisticated equilibria.

Research paper thumbnail of On the Core of an Economy with Differential Information

Journal of Economic Theory, 2000

We show that the (interim) fine core of an atomless exchange economy with differential informatio... more We show that the (interim) fine core of an atomless exchange economy with differential information is a subset of the ex-post core of the economy. Moreover, the interim fine core may be empty, and therefore it may be a proper subset of the ex-post core. The inclusion relation does not hold for economies with a finite number of traders.

Research paper thumbnail of Linear measures of inequality for cooperative games

Journal of Economic Theory, 1991

We provide a self-contained axiomatization of linear inequality measures for coalitional games. A... more We provide a self-contained axiomatization of linear inequality measures for coalitional games. Adding one axiom to those of Weymark (Math. Sot. Sci. 1 (1981) 4099430), we prove that all such measures must be generalized Gini functions of the Shapley value. Also, we generalize the foregoing result to the spaces pNA(p) of non-atomic games. Journal of Economic Literature Classification Numbers: 024. 026.