Field Experiments

Abstract

The 2019 Nobel Prize in Economic Sciences, awarded to Abhijit Banerjee, Esther Duflo, and Miguel Kremer, has acknowledged the importance of field experiments in economics, and more specifically the importance of randomized field experiments (RFEs) in development economics. This chapter attempts to highlight the methodological challenges of such experiments. The claim of this chapter is that recent field experiments in economics, namely, RFEs, have succeeded in making the field vanish: they are field experiments devoid of a messy and complex environment. This is another way of framing the struggle between internal and external validity within field experiments and particularly within RFEs. Finally, the chapter develops methodological alternatives that could restore the field to RFEs, which will ensure that RFEs keep their internal validity while strengthening their external one.