NOTE: Research institutions include those with a high level of research activity or those that award at least 20 doctor's degrees per year. Relative levels of research activity for research universities were determined by an analysis of research and development expenditures, science and engineering research staffing, and doctoral degrees conferred, by field. Further information on the research index ranking may be obtained from http://www.carnegiefoundation.org/classifications/index.asp?key=798#related. Other 4-year institutions include those that award at least 50 master's degrees per year, those that primarily emphasize undergraduate education, and those that award degrees primarily in single fields of study such as medicine, business, fine arts, theology, and engineering.
SOURCE: U.S. Department of Education, National Center for Education Statistics, 2008 Integrated Postsecondary Education Data System (IPEDS), Spring 2009.