Capital social et développement : quelques éléments d'analyse

The whole work on the role of institutions and social environment in economy is gathered under the general name of social capital. In a more precise way, we can consider one agent's social capital as a social resource, resulting from the cultural and/or structural interactions with other agents (any cluster is an agent), able to generate durable externalities which affect the economic situation of all of these agents. Consequently, the heart of the analysis resides in the relational character of the concept. Indeed, since these relations take place out-market, they can generate three externalities: learning about the behaviour of agents, learning about their environment, and collective action. The two first, which refer to the concept of information, are likely to improve the welfare of agents; it is fairly accepted in economy that a quantitative and/or qualitative improvement of information allows the agents to take more efficient decisions, because better adapted to the reality of the economic situation. Concerning the third externality, collective action, the joint setting of resources makes it possible to achieve goals which bring to each individual a higher utility than the one he would get from an individual action. This is the principle of economies of scale. According to this, social capital tends to be a fundamental asset for development, but this image is only partly true. In fact, it appeared that in certain cases social capital can generate negative externalities which support social exclusion. Moreover, certain shapes of social capital can, from their " perverse " nature (for example Mafia) hinder the development process. Hence, social capital seems to be an ambivalent concept, so that the recourse to statistical instruments appears necessary to rule on the primacy of an effect on the other. Two distinct levels of analysis are considered: the microeconomic framework and the macroeconomic one; but they both share the same (direct) methodology where social capital is the principal explanatory variable of a regression model. Generally, the econometric tests underline the role of this concept in incomes growth. Therefore, it appears that social capital needs more attention in the analysis of development, and in particular with regard to the study of poverty and inequalities.(Full text in French)