When random assignment fails: Some lessons from the Minneapolis Spouse Abuse Experiment

In this paper, we consider what may be done when researchers anticipate that in the implementation of field experiments, random assignment to experimental and control groups is likely to be flawed. We then reanalyze data from the Minneapolis Spouse Abuse Experiment in a manner that explicitly models violations of random assignment. As anticipated, we find far larger treatment effects than previously reported. The techniques developed should be useful in a wide variety of settings when random assignment is implemented imperfectly.     

Random assignment without tears: how to stop worrying and love the Cambridge randomizer

Objectives  

This note describes a low-cost online portal called “the Cambridge Randomizer”, which enables treatment providers to conduct random assignment themselves, while the researcher still maintains control over the entire process and the integrity of the allocation process.