Binned Kepler photometry (blue dots) for KOI populations above/below the period–radius valley (APRV/BPRV; top/bottom), with refraction simulations overlaid for 2, 4, 10, and 30 g mol^–1. The black vertical lines indicate ingress and egress, between which all in-transit data has been excised for clarity. Contrary to expectations of the APRV population possessing inflated, low-molecular-weight atmospheres, the 2 g mol^–1 model atmosphere poorly represents the binned APRV data and is instead better fit between the 4 and 10 g mol^–1 models. The BPRV population behaves as we expected, being relatively flat throughout.