In this paper, we reconsider the concept of Berge equilibrium. In a recent work, Colman et al. [(2011) J. Math. Psych.55, 166–175] proposed a correspondence for two-player games between Berge and Nash equilibria by permutation of the utility functions. We define here more general transformations of games that lead to a correspondence with Berge and Nash equilibria and characterize all such transformations.

This paper analyzes a semicollusive, differentiated duopoly. Firms first compete in cost reducing R&D and then cooperate on the output market. The sharing of the joint profit on the output market is modeled as a Nash bargaining game. We study an asymmetric setting in which one firm has a lower unit cost of production than the other firm, before any R&D expenditures. If firms do not agree on how to share their joint profit, they play a noncooperative Nash equilibrium. Assuming linear demand functions, we show that the Nash bargaining outcome is independent of whether firms play a Cournot or a Bertrand Nash equilibrium, as long as both firms supply positive outputs in these equilibria. If the two products are sufficiently differentiated, there is a unique equilibrium in which both firms supply a positive output, and in which the low cost firm always invests more in R&D than the high cost firm. If the two products are not very differentiated, and if the difference in unit costs between the two firms is not too large, there exist two equilibria. In each of these equilibria only one firm supplies a positive output. This can be the low cost or the high cost firm. In the latter case, the initially high cost firm invests so much in R&D that its unit cost after R&D is lower than that of the other firm. This firm then leapfrogs the other firm. If the two products are very similar and if firms apply Bertrand strategies when disagreeing, there exist equilibria in which only one firm supplies a positive output, while in the noncooperative Nash equilibrium that same firm can prevent the other firm from entering the market. We show that, in the context of the Nash bargaining model, this latter firm still has the power to claim a share of the joint profit.

The model proposed in this paper investigates a differential Cournot oligopoly game with nonrenewable resource exploitation, in which each firm may exploit either its own private pool or a common pool jointly with the rivals. Firms use a deterministic technology to invest in exploration activities. There emerges that (i) the individual exploration effort is higher when each firms has exclusive rights on a pool of its own, and (ii) depending on whether each firm has access to its own pool or all firms exploit a common one, the aggregate exploration effort is either increasing or constant in the number of firms.

The topic is two-fold. First, we prove the convexity of Owen's Airport Profit Game (inclusive of revenues and costs). As an adjunct, we characterize the class of 1-convex Airport Profit Games by equivalent properties of the corresponding cost function. Second, we classify the class of 1-convex Bankruptcy Games by solving a minimization problem of its corresponding gap function.

Given a linear transformation L on a finite dimensional real inner product space V to itself and an element q ∈ V we consider the general linear complementarity problem LCP (L, K, q) on a proper cone K ⊆ V. We observe that the iterates generated by any closed algorithmic map will converge to a solution for LCP (L, K, q), whenever L is strongly monotone. Lipschitz constants of L is vital in establishing the above said convergence. Hence we compute the Lipschitz constants for certain classes of Lyapunov, Stein and double-sided multiplicative transformations in the setting of semidefinite linear complementarity problems. We give a numerical illustration of a closed algorithmic map in the setting of a standard linear complementarity problem. On account of the difficulties in numerically implementing such algorithms for general linear complementarity problems, we give an alternative algorithm for computing the solution for a special class of strongly monotone semidefinite linear complementarity problems along with a numerical example.

As most of the supply chains in practice are decentralized, a key issue in supply chain management is to study the coordination of supply chain. The interactions among players are typically of two types, viz. vertical competition and horizontal competition. We use a game theoretic framework to analyze a two-stage supply chain. The supply chain is modeled as a Stackelberg game with a manufacturer as leader and multiple retailers as followers. We consider multiple retailers competing on quantities (Cournot competition) and study its impact on manufacturer's equilibrium decisions and profits. We show that the wholesale price contract does not achieve Nash equilibrium when retailers offer uniform pricing. On the other hand, in case of perfect price discrimination we prove the existence of unique Nash equilibrium in both deterministic and stochastic demand set-up. Under stochastic demand set-up, we consider information asymmetry between the manufacturer and retailers with respect to demand signal. Furthermore, we show the retailers' selling effort boost up the sales. As variance of sales can hurt the manufacturer's production decisions badly, we conjecture that the manufacturer can offer a retailer incentive contract which can manipulate retailers' equilibrium decision.

We propose a theory of the interaction between knowledge and games. Epistemic game theory is of course a well-developed subject but there is also a need for a theory of how some agents can affect the outcome of a game by affecting the knowledge which other agents have and thereby affecting their actions. We concentrate on games of incomplete or imperfect information, and study how conservative, moderate, or aggressive players might play such games. We provide models for the behavior of a knowledge manipulator who seeks to manipulate the knowledge states of active players in order to affect their moves and to maximize her own payoff even while she herself remains inactive, except for influencing the states of knowledge of the other players.

A Lyapunov-like (linear) transformation L on a Euclidean Jordan algebra V is defined by the condition [Formula: see text]where K is the symmetric cone of V. In this paper, we give an elementary proof (avoiding Lie algebraic ideas and results) of the fact that Lyapunov-like transformations on V are of the form La+ D, where a ∈ V, D is a derivation, and La(x) = a ◦ x for all x ∈ V.

This paper contains a survey of cooperative game theory applied to a sports environment. The variety of these applications serves us as a proof of the strength of cooperative game theory introducing successful strategies in sports and explaining the behavior of different actors.

The purpose of this paper is to review some recent applications of coalitional games in medical research, and to illustrate some related open questions. We point out the fact that many problems which are still object of debate deal with the computation, the statistical comparison and the interpretation of solutions of coalitional games defined on large biological data-sets.