Rebecca Firestone: J-PAL, has changed the conversation in global development by conducting randomized evaluations of development programs. What is a “randomized evaluation” and why is it important?
Rachel Glennerster: Randomized evaluation in development draws on the concept of a randomized clinical trial, but adapted to a development context. What we often do is work with people who are implementing programs, and encourage them to select more areas than they were planning to work with and randomize who receives the program. If they’re rolling it out over time, we randomize when communities get the program.
That allows you to compare those who have received the program with those who haven’t, or haven’t yet, received the program, to isolate the impact of the program from all the other things that are going on. And there are lots of things going on in developing countries – countries are growing, there are droughts, etc. This makes it hard to distinguish what is the effect of a program and what is the effect of all the other things happening at the same time. By creating a comparison group that is likely to be the same statistically as the group who gets the program, you can know that any difference that you find is due to the program.
RF: What is the value of randomized evaluations for development policy and program design?
RG: I come from the position of having been a policymaker before I joined J-PAL, so I’m very conscious of the fact that policymakers constantly have to make choices. There are a lot of things that we want to do, but we only have the money and capacity to do a relatively small number of them. So it’s important that we put resources where they are most useful and where they can have the biggest impact. Certainly, as a policymaker myself, I always found that I was having to make decisions without enough evidence. Providing policymakers and NGOs with information on what’s the most cost-effective approach, what actually changes in people’s lives if you spend money this way versus that way is very important if we’re going to reduce poverty.Read More