The role of players’ identification in the population on the trusting and the trustworthy behavior an experimental investigation

We study to what extent identification does matter for trustfulness and trustworthiness to emerge in a population of players. Our experimen- tal protocol is designed for isolating the effects of trustees’ identification. Trustees’ identification is a necessary condition for introducing a reputation mechanism. We run three treatments. In each treatment groups 6 players interact repeatedly and randomly and play a 30 periods investment game (Berg & al. 1995). In the first treatment players can’t identify each other, in the second one players can identify each other as trustee and in the third one players identify each other both as trustee and trustor. We show that, according to the expectation, trustees’ identification has a positive effect on reciprocity. However it doesn’t affect the average trust in the population. Trust is significantly higher than in the complete anonymous treatment only when players identify each other in both roles. We show that this enhance of trust is the result of mutual trust-reciprocity relationships formation.

Tensor fields of mixed Young symmetry type and N-complexes

We construct $N$-complexes of non completely antisymmetric irreducible tensor fields on $\mathbb R^D$ which generalize the usual complex $(N=2)$ of differential forms. Although, for $N\geq 3$, the generalized cohomology of these $N$-complexes is non trivial, we prove a generalization of the Poincar\'e lemma. To that end we use a technique reminiscent of the Green ansatz for parastatistics. Several results which appeared in various contexts are shown to be particular cases of this generalized Poincar\'e lemma. We furthermore identify the nontrivial part of the generalized cohomology. Many of the results presented here were announced in [10].Comment: 47 page

Quantum revival for elastic waves in thin plate

Quantum revival is described as the time-periodic reconstruction of a wave packet initially localized in space and time. This effect is expected in finite-size systems which exhibits commensurable discrete spectrum such as the infinite quantum well. Here, we report on the experimental observation of full and fractional quantum revival for classical waves in a two dimensional cavity. We consider flexural waves propagating in thin plates, as their quadratic dispersion at low frequencies mimics the dispersion relation of quantum systems governed by Schr\"{o}dinger equation. Time-dependent excitation and measurement are performed at ultrasonic frequencies and reveal a periodic reconstruction of the initial elastic wave packet.Comment: submitted to the special issue of EPJ ST in honor of scientific legacy of Roger Maynar

Homogeneous algebras

Various concepts associated with quadratic algebras admit natural generalizations when the quadratic algebras are replaced by graded algebras which are finitely generated in degree 1 with homogeneous relations of degree N. Such algebras are referred to as {\sl homogeneous algebras of degree N}. In particular it is shown that the Koszul complexes of quadratic algebras generalize as N-complexes for homogeneous algebras of degree N.Comment: 24 page

A method to Formalise the Rapid Prototyping Process

Facing the increasing complexity of the product design area, (reduction of cycle times, introduction of simultaneous engineering, introduction of digital mock-up, ... ) a research department which wants to define a rapid prototyping process is confronted to the problem of the tools’ choice. Therefore, we will propose in this article, a method allowing to conceive such a process. In a first chapter, we present the rapid prototyping area in the product design environment, in a second chapter we will propose our method illustrated by an industrial case

Optimization incentive and relative riskiness in experimental coordination games

We compare the experimental results of three stag-hunt games. In contrast to Battalio et al. (2001), our design keeps the riskiness ratio of the payoff-dominant and the risk-dominant strategies at a constant level as the optimisation premium is increased. We define the riskiness ratio as the relative payoff range of the two strategies. We find that decreasing the riskiness ratio while keeping the optimization premium constant increases sharply the frequency of the risk-dominant strategy. On the other hand an increase of the optimization premium with a constant riskiness ratio has no effect on the choice frequencies. Finally, we confirm the dynamic properties found by Battalio et al. that increasing the optimization premium favours best-response and sensitivity to the history of play.