Mesurer le juste prix des produits issus d'une filière « commerce équitable local » : principes, enjeux et limites épistémologiques d'une approche

A lot of socio-political and economic projects are emerging, these last years, which promote the development of a «local fair trade». Thus, the purpose is an ecological embeddedness of the fair trade, which minimise the negatives externalities of the goods transports, and which aims to preserve social and environmental amenities. The question of the «fair price» of this new offer is posed. This article aims to analyse, in epistemological terms, the concept of fair price; then, to examine the theoretical foundations of the contingent valuation methods, ordinary used to calculate the value of nonmarketed goods, or of non-yet-marketed goods - like those here examined; then to show that consumers are not how they are supposed to be : they are more consumers than consumers/citizens. So, their altruism is mixed, and not pure, as waited. This characteristic biases the collected data on the market opportunities, and biases their interpretations. These biases are here studied.