We find that reductions in traffic congestion generated by E-ZPass reduced the incidence of prematurity and low birth weight among mothers within 2km of a toll plaza by 6.7-9.1% and 8.5-11.3% respectively, with larger effects for African-Americans, smokers, and those very close to toll plazas. There were no immediate changes in the characteristics of mothers or in housing prices in the vicinity of toll plazas that could explain these changes, and the results are robust to many changes in specification. The results suggest that traffic congestion is a significant contributor to poor health in affected infants. Estimates of the costs of traffic congestion should account for these important health externalities.
The interesting thing is that I read this paper a while ago—earlier this year, or even late last. Well, maybe not this version of the paper, but an earlier version of it which also showed significant positive results. And it gets me thinking about how we deal with research.
Because the past six months or so—since the previous version—are six months in which this information apparently didn’t get disseminated to the Chris Blattmans and Kevin Drums of this world, six months during which uninformed people have bought houses near non-EZ-Pass toll plazas, six months during which every Republican candidate for the House or Senate not named Mark Kirk has spoken as if since climate change is not real, and therefore there are no possible reasons to reduce emissions. (As an aside, that the glorious liberal days of IN-9 are when Lee Hamilton seat for as long as he wanted it is an indicator of discourse shift, as this blog’s pretense to being “left of center” makes clear.)
In a limited sense, that’s probably as it should be. People who knew about the paper read it, sent comments to the authors, asked questions, suggested changes and the refinements. I’m certain the current version is a better paper than the one I read, with better details.
But there is likely someone who, in the past six months, bought a house near a toll plaza that doesn’t have E-Z Pass exits, thinking she was going to raise her soon-to-be-born child in a better environment than an apartment who would have liked to have known about this study, instead of ending up with “Buyer’s Remorse” in a real—not just an economic or psychological—sense.
As long as research is delayed by details and false narratives remain information-free, markets will remain inefficient. And people will have what economists gracefully call “suboptimal outcomes.” Such as “prematurity and low birth weight,” neither of which is a positive indicator for future success and earnings.