Computing all solutions of Nash equilibrium problems with discrete strategy sets

The Nash equilibrium problem is a widely used tool to model non-cooperative games. Many solution methods have been proposed in the literature to compute solutions of Nash equilibrium problems with continuous strategy sets, but, besides some specific methods for some particular applications, there are no general algorithms to compute solutions of Nash equilibrium problems in which the strategy set of each player is assumed to be discrete. We define a branching method to compute the whole solution set of Nash equilibrium problems with discrete strategy sets. This method is equipped with a procedure that, by fixing variables, effectively prunes the branches of the search tree. Furthermore, we propose a preliminary procedure that by shrinking the feasible set improves the performances of the branching method when tackling a particular class of problems. Moreover, we prove existence of equilibria and we propose an extremely fast Jacobi-type method which leads to one equilibrium for a new class of Nash equilibrium problems with discrete strategy sets. Our numerical results show that all proposed algorithms work very well in practice

High p_T suppression of Lambda and K0s in Pb-Pb collisions at sqrt(s_NN)= 2.76 TeV with ALICE

The nuclear modification factors R_AA and R_CP of Lambda and K0s in Pb-Pb collisions at sqrt(s_NN)= 2.76 TeV measured by ALICE at LHC are presented. In central collisions a strong suppression at high p_T (p_T > 8 GeV/c) with respect to pp collisions is observed. The p_T region below is dominated by an enhancement of Lambda over the suppressed K0s. The results are compared to those for charged hadrons and to Lambda from lower collision energies.Comment: 4 pages, 6 figures, proceedings to Quark Matter 201

The Trade-Climate Nexus: Assessing the European Union’s Institutionalist Approach. College of Europe EU Diplomacy Paper 04/2019

The European Union (EU) is considered a global leader both in trade and climate policies. Nonetheless, trade liberalisation has been widely criticised for its negative effects on the environment and for directly contributing to the rising levels of annual greenhouse gas emissions. This paper addresses the trade-climate nexus by assessing to what extent the EU is effectively integrating its environmental objectives within its trade policies. First, the legal spaces for the EU’s action in this policy nexus are identified. Second, the analysis looks into how effectively the EU is achieving its own set of objectives for trade and climate. The assessment draws on an innovative analytical matrix examining four Trade-Climate Agenda items: (i) international competitiveness, (ii) climate-friendly goods and services, (iii) international aviation and maritime shipping, and (iv) product labelling and standards. The paper then evaluates to what extent the externalisation mechanisms of Manners’ ‘Normative Power Europe’ and Damro’s ‘Market Power Europe’ are deployed in order to achieve the above objectives. The findings show that the EU’s performance in the effective management of the nexus is overall moderate to weak