Good Casual Analysis from Bad

Recently, I wrote about Tatu Westling's paper on "male organ" length and economic growth. I argued that it was likely a case of omitted variables bias and there wasn't real causality here. And certainly this relationship wasn't stable over time. This paper did get a lot of media coverage and hence a lot of downloads. Now Westling has teamed up with a fellow student to analyse the incident. They find that other papers on their website also experienced an increase in downloads which can be attributed to a spillover effect from the interest in Westling's paper. They use differences in differences and regression discontinuity methods. This sounds pretty solid as the interest in the paper in question was a pretty exogenous shock. So having star papers in your working paper series will help increase downloads of other papers. This is similar to the Matthew effect in citations. Authors with lots of citations tend to get more and more citations and publishing a landmark paper will result in your other papers getting cited more too.