Post by Eva Vivalt, @evavivalt.

AidGrade is starting another crowdfunding effort. You might wonder: why now? You’re not new so why should I support you?

There have been a lot of interesting things coming out of this work. Dare I say, more interesting than when we launched last year.

For one, we are looking more closely at the issue of generalizability. How much can you generalize from an impact evaluation’s results and are there any factors that improve your ability to make out-of-sample predictions?

This is a huge, important topic, and without having painstakingly collected the data from hundreds of impact evaluations, I’m not sure how you could answer it. Preliminary working paper which contains errors here. By adding impact evaluations to the data set, we’ll be able to say a lot more.

We’re expanding our previous analyses to look more closely at study quality and will put out white papers on each of the topics.

And we are looking at the issue of specification searching and publication bias. So far, it seems like it’s not as bad as you would think.

So, yes, we’re asking for more money. It’s because we’re doing a whole lot more than we did when we started (even more at the link). And frankly, it’s not a lot of money relative to the importance of the questions answered, and you will not find such a cost-effective group elsewhere.

A lot of people seem to like to focus on what we know. I’d like to focus for a second on what we don’t know. Particularly on the big, important questions which we can, with your help, answer.

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