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- RE: Hydraulic fracturing and infant health: New evidence from Pennsylvania
I congratulate the authors on a very well-specified and comprehensive model of the potential effect of fracking on infant health.
However, I am left with the sense that either or both of location-specific effects or maternal fixed or time-variant effects could explain an unknown portion of the effect found here.
Re location-specific effects where unique aspects of the location may independently affect maternal or infant health: if this is true then the research question is fundamentally unidentified.
Re maternal fixed effects: I realize that time invariant effects are washed out by that particular specification in the model but worry (as the authors acknowledge) that in practice this is tough to do. The relevant margin on which these effects are being identified in that small sub-sample may intrinsically be different from others and not generalizable.
I realize these concerns are not addressable any further than the authors already have done, but wish that the popular media accounts of this research would caveat results more.
Thanks and regards
Marco D. HueschCompeting Interests: None declared.
