I actually don't think that 3 has much explanatory power. Rather, I think the bulk of the variance is beyond 10 years. Yale's strongest suit is likely professional programs like law and medicine. These are high paying professions, but they require additional years of education beyond a 4 year bachelor's, and that subtracts earning years from the 10 year cutoff.
I don't know much about Rice, but I suspect it's particular problem is being a highly selective school in a low cost of living area. If an average Rice CS student randomly selected into other schools with comparable SAT scores, they'd be going to a much more expensive region, and their controlling for location may not sufficiently model how a CS degree differs from community college nursing.