The Success of Randomized Controlled Trials: A Sociographical Study of the Rise of J-PAL to Scientific Excellence and Influence

Randomized controlled trials (RCTs) are a method to assess impact that has become increasingly popular over the last fifteen years, particularly as a result of the work done by Esther Duflo and her Poverty Action Lab (J-PAL), an or-ganization devoted to the promotion of randomization. This article aims to explore and understand this success by using an in-depth sociographical study of the J-PAL and a network analysis of economists who use RCT. J-PAL appears to be a concentration of educational and academic capital that give great legitimacy to the RCT method. The network is controlled by certain leaders who are able to diffuse the J-PAL approach to RCTs. Furthermore, this article argues that it is necessary to go beyond the intrinsic quality of this method to explain how it became so popular.