Du refus de vente au don: une explication de la formation du prix par l´affect[From rejection of exchange to gift: regard as an explanation of prices]

This paper aims at explaining observed distinct prices announced by a single supplier for an identical product, in an illegal framework. The modeling proposed here examines an augmented mark-up pricing equation for oligopolistic markets that includes a function of social discrimination. The latter is justified through both sociologic and anthropologic approaches which are taken into account the importance of the degree of personalization that characterizes any exchange, either merchant or non merchant. Such a perspective leads us to conceive prices as transmitting not only a vector of information but also a vector of affect that signals the level of social integration for participants interacting into personal exchanges. Without a legal benchmark, individuals are differentiated by their position in social networks, including family. Given the function of social discrimination, a more complete explanation can be displayed in terms of why a continuum of prices exists for a same illegal good for instance swindling prices, competitive market prices, non-market prices etc. Therefore, by converting each price in a singular expression of a particular exchange, we demonstrate that belonging or not to a social network impacts on price formation in illegal markets, even provides a better understanding of some extreme cases such as refusal of sale or gift exchange.