Proof-theoretic Analysis of Rationality for Strategic Games with Arbitrary Strategy Sets

In the context of strategic games, we provide an axiomatic proof of the statement Common knowledge of rationality implies that the players will choose only strategies that survive the iterated elimination of strictly dominated strategies. Rationality here means playing only strategies one believes to be best responses. This involves looking at two formal languages. One is first-order, and is used to formalise optimality conditions, like avoiding strictly dominated strategies, or playing a best response. The other is a modal fixpoint language with expressions for optimality, rationality and belief. Fixpoints are used to form expressions for common belief and for iterated elimination of non-optimal strategies.Comment: 16 pages, Proc. 11th International Workshop on Computational Logic in Multi-Agent Systems (CLIMA XI). To appea

Consistent Treatment of Relativistic Effects in Electrodisintegration of the Deuteron

The influence of relativistic contributions to deuteron electrodisintegration is systematically studied in various kinematic regions of energy and momentum transfer. As theoretical framework the equation-of-motion and the unitarily equivalent S-matrix approaches are used. In a (p/M)-expansion, all leading order relativistic $\pi$-exchange contributions consistent with the Bonn OBEPQ model are included. In addition, static heavy meson exchange currents including boost terms, $\gamma\pi\rho/\omega$-currents, and $\Delta$-isobar contributions are considered. Sizeable effects from the various relativistic two-body contributions, mainly from $\pi$-exchange, have been found in inclusive form factors and exclusive structure functions for a variety of kinematic regions.Comment: 41 pages revtex including 15 postscript figure

Optimal money burning: Theory and application to corporate dividends

We explore signaling behavior in settings with a discriminating activity and several costly nondiscriminating (“money-burning”) activities. Existing theory provides no basis for selecting one method of burning money over another. When senders have better information about activity costs than receivers, each sender's indifference is resolved, the taxation of a money-burning signal is potentially Pareto-improving, and the use of the taxed activity becomes more widespread as the tax rate rises. We apply this theory to dividend signaling. Its central testable implication—that an increase in the dividend tax increases the likelihood of dividend payout—is verified empirically

Assessing the Impact of Antitrust Intervention by the Italian Competition Authority

impact assessment, merger, anticompetitive agreements, advocacy, baby milk, fresh milk, K21, L40, L66,

Near-Strong Equilibria in Network Creation Games

We introduce a new solution concept for games, near-strong equilibrium, a variation of strong equilibrium. Previous work has shown the existence of 2-strong pure strategy equilibrium for network creation games with 1 < α < 2 and that k-strong equilibrium for k ≥ 3 does not exist. In this paper we show that 3-near-strong equilibrium exists, and provide tight bounds on existence of k-near-strong equilibria for k ≥ 4. Then we repeat our analysis for correlated mixed strategies, where we show that, surprisingly, 3-correlated-strong equilibrium exists, and also show bounds for existence of correlated k-strong equilibria. Moreover, the equilibrium profile can be arbitrarily close to the social optimum. For both pure and correlated settings, we show examples where no equilibrium exists. On the conceptual level, our work contributes to the recent literature of extensions of strong equilibrium, while providing positive results for stability against group deviations in one of the basic settings discussed in the algorithmic game theory literature.