Randomised control trials (RCT)

Experiments in which a policy change is applied to a randomly selected subset of people, in order to isolate its economic effects. Most examples have been in developing countries. Abhijit Banerjee, Esther Duflo and Michael Kremer shared the 2019 Nobel prize for their work on RCTs (for more details, see this article and this book review). Some have questioned the ethics of such trials (see article).