Incorporating ethics and welfare into Randomized experiments (by Yusuke Narita)


Yusuke Narita


Randomized controlled trials (RCTs) enroll hundreds of millions of subjects and involve many human lives. To improve subjects’ welfare, I propose a design of RCTs that I call Experiment-asMarket (EXAM). EXAM produces a welfare-maximizing allocation of treatment-assignment probabilities, is almost incentivecompatible for preference elicitation, and unbiasedly estimates any causal effect estimable with standard RCTs. I quantify these properties by applying EXAM to a water-cleaning experiment in Kenya. In this empirical setting, compared to standard RCTs, EXAM improves subjects’ predicted well-being while reaching similar treatment-effect estimates with similar precision.