A note on methodology: 4-year colleges and universities.

To establish the set of colleges included in the rankings, we started with the 1,860 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 2017. We then excluded 356 baccalaureate and baccalaureate/associate's-level colleges that reported that at least half of the undergraduate degrees awarded in 2012 were below the bachelor's-degree level, as well as twenty colleges with fewer than 100 undergraduate students in any year they were open between fall 2013 and fall 2015, and an additional seventy-eight colleges with fewer than seventy-five students in the federal graduation rate cohort (first-time, full-time students) between 2013 and 2015.

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). This resulted in a final sample of 1,404 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 use an average of the three most recent years of data in an effort to get a better picture of a college's performance rather than...