Car seats as contraception
I read through the underlying paper, and I don&#x27;t quite understand their methodology. It seems like they&#x27;re taking a bucketload of demographic information and then trying to control for every other possible factor that could affect fertility rates to isolate the effect of car seat laws. I&#x27;m skeptical that it&#x27;s even possible to control for all of those variables. Even assuming that they perfectly model the factors they do account for, it&#x27;s perfectly possible that there are more underlying factors.<p>Additionally, interpreting the results as t-statistics doesn&#x27;t really tell us very much, as the variation between model and reality could easily be noise from the control variables rather than from a relationship between car seat laws and fertility.<p>I&#x27;m not saying the paper doesn&#x27;t have any merit at all--I think the idea is quite interesting. I am just skeptical of inferring anything from the results, given that the methodology is very poorly described (and is so error-prone).