The question of efficiency of market organization is an important one in economics. When theoretical results suggest the dominance of auctions, empirical studies present more mitigated results putting forward that the global efficiency depends on agents' characteristics and market environment....

Addressing issues of social diversity, we introduce a model of housing transactions between agents who are heterogeneous in their willingness to pay. A key assumption is that agents' preferences for a location depend on both an intrinsic attractiveness and on the social characteristics of the...

Starting from some regularities of the Boulogne s/mer fish market, the model proposed here shows that in many circumstances the collective behavior may be ‘reasonable’ whereas the individuals may not be so. The properties which are empirically clear at the aggregate level are not necessarily...

The empirical analysis of fish markets always reveals strong price dispersion for homogeneous or very similar goods. The problem is how to explain this price dispersion on a market where there is no evident arbitrage. Explanations proposed by different authors include differences in...

[eng] Champagne is a product whose quality is difficult to evaluate, even a posteriori, by the consumer. Firms exploit this particularity and invest in reputation either by producing a wine of high quality or by means of public recognition through advertising. Thus, it is optimal for a producer...

[fre] L'organisme de capital-risque qui a investi dans une jeune entreprise innovante a deux modes de sortie : l'introduction en bourse (marché IPO) et le rachat par une grande firme (M&A). Le marché financier concentre l'attention des professionnels qui ont vu en lui un Eldorado. Sa...

Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact...

Some universal features are independent of both the social nature of the individuals making the decision and the nature of the decision itself. On this basis a simple magnet like model is built. Pair interactions are introduced to measure the degree of exchange among individuals while...

A modified version of a finite random field Ising ferromagnetic model in an external magnetic field at zero temperature is presented to describe group decision making. Fields may have a non-zero average. A postulate of minimum inter-individual conflicts is assumed. Interactions then produce a...

The origins of Sociophysics are discussed from a personal testimony. I trace back its history to the late 1970s. My 20 years of activities and research to establish and promote the field are reviewed. In particular, the conflicting nature of Sociophysics with the physics community is revealed...