Chris Blattman just dropped something of a bombshell on experiments as dissertation projects:

the market [for field experiments] is getting very crowded, and there are a million in the pipeline. So this is a poor product placement. The premium on other types of research is high and getting higher.

This voices a concern that I’ve been mulling over for years, ever since I completed my first (and only to date) experiment. This was a great second project, but it benefited from being on the early side of the wave of experiments in comparative politics, when the field was much less crowded. It also would have been nearly impossible to pull off as a dissertation project because it required lots of time, a rich network of research contacts in Indonesia, a willingness to coauthor, and a whole lot of luck. It’s also worth noting that as a survey experiment, it was probably easier to conduct than the field experiments that are the subject of Blattman’s post. (And as anyone who has asked me in the past two years knows, I very much do not advise building a dissertation around a survey experiment.)

But what is most interesting about the quote above is the statement “the premium on other types of research is high and getting higher.” Here I’m not so sure, and I want to know more. What other types? Let’s focus here on the fields of comparative politics and the political economy of development, the audience to which Blattman’s post will most resonate. These fields are certainly not going back to the days in which cross-national regressions are dominant, so it can’t just mean that. I always enjoy reading big and messy structured macrohistorical comparisons, but I don’t detect a big premium on them. So I’m left wondering if others believe there is a growing premium on non-experimental research in CP and PED these days, because I sense that this would be a fairly striking departure from recent trends.