RCTs

It is a Wild West out there when it comes to testing for attrition in field experiments. Researchers use different tests, describe them with different terms, and somehow always find a way to conclude that attrition is not a problem in their case. So I was happy to read Testing Attrition Bias in Field Experiments by Dalia Ghanem, Sarojini Hirshleifer and Karen Ortiz-Becerra (Journal of Human Resources, 2026; ungated version). It turns out I was doing it wrong. Chances are, so are you. ...

Even if you ARE part of government, evidence-based policy change is hard. It takes strategy, patience, and courage. I have had the privilege of collaborating with researchers at South Africa’s Department of Basic Education (DBE) for over a decade, iteratively experimenting with ways to improve foundational literacy. At a recent Centre for the Study of African Economies (CSAE) panel, my long-time collaborator Nompumelelo (Mpumi) Mohohlwane, the new Director for Reading there, offered insights on how evidence-based change actually happens from inside government. What follows draws on her remarks — along with reflections from Stephen Taylor, who leads the DBE’s Research, Monitoring, and Evaluation unit and this research program. ...