An Experimental Investigation of Colonel Blotto Games

"This article examines behavior in the two-player, constant-sum Colonel Blotto game with asymmetric resources in which players maximize the expected number of battlefields won. The experimental results support all major theoretical predictions. In the auction treatment, where winning a battlefield is deterministic, disadvantaged players use a 'guerilla warfare' strategy which stochastically allocates zero resources to a subset of battlefields. Advantaged players employ a 'stochastic complete coverage' strategy, allocating random, but positive, resource levels across the battlefields. In the lottery treatment, where winning a battlefield is probabilistic, both players divide their resources equally across all battlefields." (author's abstract)"Dieser Artikel untersucht das Verhalten von Individuen in einem 'constant-sum Colonel Blotto'-Spiel zwischen zwei Spielern, bei dem die Spieler mit unterschiedlichen Ressourcen ausgestattet sind und die erwartete Anzahl gewonnener Schlachtfelder maximieren. Die experimentellen Ergebnisse bestätigen alle wichtigen theoretischen Vorhersagen. Im Durchgang, in dem wie in einer Auktion der Sieg in einem Schlachtfeld deterministisch ist, wenden die Spieler, die sich im Nachteil befinden, eine 'Guerillataktik' an, und verteilen ihre Ressourcen stochastisch auf eine Teilmenge der Schlachtfelder. Spieler mit einem Vorteil verwenden eine Strategie der 'stochastischen vollständigen Abdeckung', indem sie zufällig eine positive Ressourcenmenge auf allen Schlachtfeldern positionieren. Im Durchgang, in dem sich der Gewinn eines Schlachtfeldes probabilistisch wie in einer Lotterie bestimmt, teilen beide Spieler ihre Ressourcen gleichmäßig auf alle Schlachtfelder auf." (Autorenreferat

Generalizations of the General Lotto and Colonel Blotto Games

In this paper, we generalize the General Lotto game (budget constraints satisfied in expectation) and the Colonel Blotto game (budget constraints hold with probability one) to allow for battlefield valuations that are heterogeneous across battlefields and asymmetric across players, and for the players to have asymmetric resource constraints. We completely characterize Nash equilibrium in the generalized version of the General Lotto game and then show how this characterization can be applied to identify equilibria in the Colonel Blotto version of the game. In both games, we find that there exist sets of non-pathological parameter configurations of positive Lebesgue measure with multiple payoff nonequivalent equilibria

Wave Guide Imaging through Time Domain Topological Energy

AbstractTime Domain Topological Energy (TDTE), uses a measure of the reflected ultrasonic field on an array of transducers placed on the boundary of the imaged medium. Two numerical determinations (direct and adjoint problems) of the acoustical field inside a reference medium are then necessary to obtain the image by computing the topological energy. This technique comes from the field of shape optimisation and mathematical developments for Non Destructive Testing and have shown close links with Time Reversal (TR) concepts. TR mirrors have been employed for various applications in a wide number of situations including wave guides (WG) where very good refocalisation performances have been obtained with a reduced number of transducers instead of an array. Moreover recent works have enlighten that the reverberation properties of a WG allow to re-focalise using TR with only one transducer. For TDTE imaging we choose to model a single transducer placed at one end of a wave guide. The boundaries of the WG create virtual sources that can be understood as a virtual array of transducers. Results obtained numerically for imaging using both TDTE and one transducer in a wave guide with increasing complexity : a hard spherical object and a set of three identical objects placed at the angles of an equilateral triangle are presented and preliminary experimental results are discussed

PREVALENCE OF VERTEBRAL FRACTURES IN ANKYLOSING SPONDYLITIS: A META-ANALYSIS

Congress of the European-League-Against-Rheumatism (EULAR), Amsterdam, NETHERLANDS, JUN 13-16, 201