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

To establish the set of colleges included in the rankings, we started with the 1,739 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 2015 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 2018. We then excluded 179 baccalaureate and baccalaureate/associate's-level colleges which reported that at least half of the undergraduate degrees awarded between 2013 and 2015 were below the bachelor's-degree level, as well as twenty-four colleges with fewer than 100 undergraduate students in any year they were open between fall 2014 and fall 2016 and an additional eleven 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 thirty-two colleges for not having data on at least one of our key social mobility outcomes (percent Pell, graduation rate, or net price).This resulted in a final sample of 1,488 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).The data was also adjusted to account for statistical outliers. No college's performance in any single area was allowed to exceed five standard deviations from the mean of the data set. All measures...