L'apport de la psychologie sociale à l'analyse économique

The aim of this paper is to understand the crucial role of Social Psychology in economic analysis. Firstly, we present the scientific domain related to Social Psychology, as well as its methods, preferred topics and analytical tools. Secondly, we analyze how the introduction of social psychology interpersonal concepts (cognitive dissonance, heuristics, diffusion of responsibility, fundamental attribution error, magical thinking, false consensus bias, belief in a just world) into economic analysis can improve pure rational decision theory. Thirdly, we focus on the fundamental role of social influence (conformism, leadership), group formation (identity, discrimination) and social ties (family, friends), on individual and collective economic decisions. Our review shows that collaboration between economists and social psychologists can lead to new experimental results and can substantially improve economic behavioural models. Cooperation between the two disciplines thus leads to new useful political tools (framing, persuasion and social norms) which can be useful for public decision-makers.