An Academic Does the Right Thing

A few years back Dubner and I wrote a piece on Slate heralding a remarkable young economist, Emily Oster. She has continued to do great work.

She also has done something incredibly rare for an academic economist: she has admitted she was wrong.

In places like India and China, there are many “missing women.” In other words, the sex ratios in those places are out of whack. This is especially true now with the availability of ultrasound machines to aid in sex-selective abortion, but it was true long before that technology became available.

Emily wrote a paper arguing that high rates of Hepatitis B in China explained a large part of the missing women puzzle. Medical data suggested women with Hepatitis B gave birth to more sons — many women in China are infected, thus too many sons. It seemed like a crazy theory when I first heard it, but she put together extremely compelling evidence from a variety of sources to support her argument. Eventually we published it in the Journal of Political Economy, where I was an editor.

Then along came a host of other academics, including my friend and former student Ming-jen Lin, who gathered data from new sources that didn’t support Emily’s conclusions. Usually, these debates become quite acrimonious and linger on until no one cares any more. Certainly no one would admit they were wrong.

Much to Emily’s credit, however, she hit on a way to run a new study that could provide a “definitive” (or as definitive as you can get with this sort of social science research). She gathered new data in China, and after she analyzed it, she found that it did not support her conclusions. So she wrote a paper saying exactly that.

I have great admiration for her doing this. I know a lot of people who wouldn’t have done the same thing. They wouldn’t have undertaken a study that could show their biggest result was wrong, and if they found a negative result, they would try to bury it.

Also, hats off to Justin Lahart at the Wall Street Journal who wrote this article on the topic. Here are the key papers.