Oligopoly Games With and Without Transferable Technologies

In this paper standard oligopolies are interpreted in two ways, namely as oligopolies without transferable technologies and as oligopolies with transferable technologies.From a cooperative point of view this leads to two different classes of cooperative games.We show that cooperative oligopoly games without transferable technologies are convex games and that cooperative oligopoly games with transferable are totally balanced, but not necessarily convex.Oligopolies;cooperative games;convexity;total balancedness

Convexity and the Shapley value in Bertrand oligopoly TU-games with Shubik's demand functions

The Bertrand Oligopoly situation with Shubik's demand functions is modelled as a cooperative TU game. For that purpose two optimization problems are solved to arrive at the description of the worth of any coalition in the so-called Bertrand Oligopoly Game. Under certain circumstances, this Bertrand oligopoly game has clear affinities with the well-known notion in statistics called variance with respect to the distinct marginal costs. This Bertrand Oligopoly Game is shown to be totally balanced, but fails to be convex unless all the firms have the same marginal costs. Under the complementary circumstances, the Bertrand Oligopoly Game is shown to be convex and in addition, its Shapley value is fully determined on the basis of linearity applied to an appealing decomposition of the Bertrand Oligopoly Game into the difference between two convex games, besides two nonessential games. One of these two essential games concerns the square of one non- essential game.Bertrand Oligopoly situation, Bertrand Oligopoly Game, Convexity, Shapley Value, Total Balancedness.

Convexity of Bertrand oligopoly TU-games with differentiated products

In this article we consider Bertrand oligopoly TU-games with differentiated products. We assume that the demand system is Shubik's (1980) and that firms operate at a constant and identical marginal and average cost. First, we show that the alpha and beta- characteristic functions (Aumann 1959) lead to the same class of Bertrand oligopoly TU-games and we prove that the convexity property holds for this class of games. Then, following Chander and Tulkens (1997) we consider the gamma-characteristic function where firms react to a deviating coalition by choosing individual best reply strategies. For this class of games, we show that the Equal Division Solution belongs to the core and we provide a sufficient condition under which such games are convex.Bertrand oligopoly TU-games; Core; Convexity; Equal Division Solution

The gamma-core in Cournot oligopoly TU-games with capacity constraints

In cooperative Cournot oligopoly games, it is known that the alpha-core is equal to the beta-core, and both are non-empty if every individual profit function is continuous and concave (Zhao 1999b). Following Chander and Tulkens (1997), we assume that firms react to a deviating coalition by choosing individual best reply strategies. We deal with the problem of the non-emptiness of the induced core, the gamma-core, by two different approaches. The first establishes that the associated Cournot oligopoly TU(Transferable Utility)-games are balanced if the inverse demand function is differentiable and every individual profit function is continuous and concave on the set of strategy profiles, which is a step forward beyond Zhao's core existence result for this class of games. The second approach, restricted to the class of Cournot oligopoly TU-games with linear cost functions, provides a single-valued allocation rule in the gamma-core called NP(Nash Pro rata)-value. This result generalizes Funaki and Yamato's core existence result (1999) from no capacity constraint to asymmetric capacity constraints. Moreover, we provide an axiomatic characterization of this solution by means of four properties: efficiency, null firm, monotonicity and non-cooperative fairness.Cournot oligopoly TU-games; gamma-core; Balanced game; NP-value; Noncooperative fairness

Stackelberg oligopoly TU-games: characterization of the core and 1-concavity of the dual game

In this article we consider Stackelberg oligopoly TU-games in gamma-characteristic function form (Chander and Tulkens 1997) in which any deviating coalition produces an output at a first period as a leader and outsiders simultaneously and independently play a quantity at a second period as followers. We assume that the inverse demand function is linear and that firms operate at constant but possibly distinct marginal costs. Generally speaking, for any TU-game we show that the 1-concavity property of its dual game is a necessary and sufficient condition under which the core of the initial game is non-empty and coincides with the set of imputations. The dual game of a Stackelberg oligopoly TU-game is of great interest since it describes the marginal contribution of followers to join the grand coalition by turning leaders. The aim is to provide a necessary and sufficient condition which ensures that the dual game of a Stackelberg oligopoly TU-game satisfies the 1-concavity property. Moreover, we prove that this condition depends on the heterogeneity of firms' marginal costs, i.e., the dual game is 1-concave if and only if firms' marginal costs are not too heterogeneous. This last result extends Marini and Currarini's core non-emptiness result (2003) for oligopoly situations.Stackelberg oligopoly TU-game; Dual game; 1-concavity

Oligopoly Games With and Without Transferable Technologies

In this paper standard oligopolies are interpreted in two ways, namely as oligopolies without transferable technologies and as oligopolies with transferable technologies.From a cooperative point of view this leads to two different classes of cooperative games.We show that cooperative oligopoly games without transferable technologies are convex games and that cooperative oligopoly games with transferable are totally balanced, but not necessarily convex.

Cournot oligopoly interval games

In this paper we consider cooperative Cournot oligopoly games. Following Chander and Tulkens (1997) we assume that firms react to a deviating coalition by choosing individual best reply strategies. Lardon (2009) shows that if the inverse demand function is not differentiable, it is not always possible to define a Cournot oligopoly TU(Transferable Utility)-game. In this paper, we prove that we can always specify a Cournot oligopoly interval game. Furthermore, we deal with the problem of the non-emptiness of two induced cores: the interval gamma-core and the standard gamma-core. To this end, we use a decision theory criterion, the Hurwicz criterion (Hurwicz 1951), that consists in combining, for any coalition, the worst and the better worths that it can obtain in its worth interval. The first result states that the interval gamma-core is non-empty if and only if the oligopoly TU-game associated with the better worth of every coalition in its worth interval admits a non-empty gamma-core. However, we show that even for a very simple oligopoly situation, this condition fails to be satisfied. The second result states that the standard gamma-core is non-empty if and only if the oligopoly TU- game associated with the worst worth of every coalition in its worth interval admits a nonempty gamma-core. Moreover, we give some properties on every individual profit function and every cost function under which this condition always holds, what substantially extends the gamma-core existence results in Lardon (2009).Cournot oligopoly interval game; Interval gamma-core; Standard gamma-core; Hurwicz criterion;

Convexity and the Shapley value in Bertrand oligopoly TU-games with Shubik's demand functions

The Bertrand Oligopoly situation with Shubik's demand functions is modelled as a cooperative TU game. For that purpose two optimization problems are solved to arrive at the description of the worth of any coalition in the so-called Bertrand Oligopoly Game. Under certain circumstances, this Bertrand oligopoly game has clear affinities with the well-known notion in statistics called variance with respect to the distinct marginal costs. This Bertrand Oligopoly Game is shown to be totally balanced, but fails to be convex unless all the firms have the same marginal costs. Under the complementary circumstances, the Bertrand Oligopoly Game is shown to be convex and in addition, its Shapley value is fully determined on the basis of linearity applied to an appealing decomposition of the Bertrand Oligopoly Game into the difference between two convex games, besides two nonessential games. One of these two essential games concerns the square of one non- essential game

Transboundary Fishery Management: A Game Theoretic Approach

A basic issue in transboundary fishery management is the new member problem. In this paper we address the problem of allocating the profits between the charter members and the entrants, once the nations concerned have expressed an interest in achieving an agreement.Using game theory we argue that in the case of independent countries adjustment from the Nash equilibrium can be achieved by means of the proportional rule.Furthermore, we propose the population monotonic allocation scheme as management rule for division of profits within a coalition. Finally, we show that the equal division of the net gain value can be used to expand a coalition.game theory;fishing industry;Nash equilibrium

Essays in Game Theory and Natural Resource Management.

This thesis presents a collection of essays in game theory with applications to environmental resource problems and their management. A major focus of these essays is related to coalitional games in which several classes of games, their properties and solution concepts are studied. Game theory is applied to international fisheries management in the context of the 1995 United Nations Agreement on the Implementation of the UN Convention on the Law of the Sea.