A NOTE ON METHODOLOGY: 4-YEAR COLLEGES AND UNIVERSITIES.

To establish the set of colleges included in the rankings, we started with the 1,732 colleges in the fifty states that are listed in the U.S. Department of Education's Integrated Postsecondary Education Data System (IPEDS) and have a 2018 Carnegie basic classification of research, master's, baccalaureate, and baccalaureate/associate's colleges, are not exclusively graduate colleges, participate in federal financial aid programs, and plan to be open in fall 2019. We then excluded 212 baccalaureate and baccalaureate/associate's-level colleges which reported that at least half of the undergraduate degrees awarded were below the bachelor's-degree level, as well as twenty-seven colleges with fewer than 100 undergraduate students in any year they were open between fall 2015 and fall 2017 and an additional four colleges with fewer than twenty-five students in the federal graduation rate cohort in 2016.

Next, we decided to exclude the five federal military academies (Air Force, Army, Coast Guard, Merchant Marine, and Navy) because their unique missions make them difficult to evaluate using our methodology. Our rankings are based in part on the percentage of students receiving Pell Grants and the percentage of students enrolled in the Reserve Officers' Training Corps (ROTC), whereas the service academies provide all students with free tuition (and thus no Pell Grants or student loans) and commission graduates as officers in the armed services (and thus not the ROTC program). Finally, we dropped an additional fifty-one colleges for not having data on at least one of our key social mobility outcomes (percent Pell, graduation rate, net price, or the number of Pell recipients earning bachelor's degrees). This resulted in a final sample of 1,431 colleges and includes public, private nonprofit, and for-profit colleges.

Our rankings consist of three equally weighted portions: social mobility, research, and community and national service. This means that top-ranked colleges needed to be excellent across the full breadth of our measures, rather than excelling in just one measure. In order to ensure that each measurement contributed equally to a college's score within any given category, we standardized each data element so that each had a mean of zero and a standard deviation of one (unless noted). Missing social mobility data (affecting less than 1 percent of all observations) were imputed and noted with "N/A" in the rankings tables. We adjusted data to...