One of the bon mots I remember from The Economist, from the days when I used to read it, is their definition of a radical: "someone we disagree with." Well, by that standard, I am less and less of a radical with almost every issue of the magazine.
The magazine's latest Economics Focus column reports on the Brookings development conference that I had to miss, but to which I contributed a paper. Their bottom line on the contribution (and limitations) of randomized field experiments follows the arguments in my paper fairly closely--down to the example of anti-malaria bed nets that I used in my paper to illustrate the problems of extending results in one specific setting (Western Kenya) to others.
The article quotes Abhijit Banerjee, who says
"the quality of the evidence that informs much of the macro-growth debates is significantly worse than the quality of the data that bears on many of the micro-policy questions”. He adds: “The beauty of randomised evaluations is that the results are what they are.” In other words, they provide hard evidence, resting on a solid empirical base.
The trouble is that the moment you take the experiment from Western Kenya and want to use it to inform policy in another setting, you need to make all kind of additional, not rigorously tested assumptions (about how similar or dissimilar the settings are and how these affect the likely outcomes). By the time the evidence is used, it has become as "soft" as many other kinds of evidence that development economists traditionally rely on.
(And before someone writes to ask how I know about this article if I do not read The Economist, the reason is that I was asked by the author to check on a quote prior to publication. Plus, I regularly Google myself of course...)