PDF here (via Innovators for Poverty Action, whose research is featured). After discussing the Karlan/Zinman study showing benefits for loans (which we summarize here), it continues: Karlan is the first to warn against extrapolating too much from a single experiment. “This is the last thing in the world that I would use to develop policy,”…
The GiveWell Blog
All Impact evaluation Posts
Microfinance/education program didn’t work as expected
A reader was good enough to send in a Lancet article (free registration required for full text) about a well-designed study of a combination microfinance/education program in South Africa. Study design, strengths and weaknesses A program consisting of both loans and group meetings was rolled out to 8 villages in rural South Africa, but the…
Surgeries performed vs. cases of blindness prevented
We’ve written before about the possibility that surgeries to correct blindness are extremely cost effective. While summarizing the evidence of effectiveness for trachoma interventions, we’ve learned more and it’s clear that equating surgeries performed with cases of blindness prevented is plain wrong. I read Trachoma: an overview, a literature review of the evidence of effectiveness…
Publication bias: Over-reporting good news
As we look for evidence-backed programs, a major problem we’re grappling with is publication bias – the tendency of both researchers and publishers to skew the evidence to the optimistic side, before it ever gets out in the open where we can look at it. It sounds too scary to be real – how can…
Beware just-published studies
A recent study on health care in Ghana has been making the rounds – first on Megan McArdle’s blog and then on Marginal Revolution and Overcoming Bias. McArdle says the study shows “little relationship between consumption and health outcomes”; the other two title their posts “The marginal value of health care in Ghana: is it…