A significant body of research shows that retention and graduation rates differ widely among various types of institutions and those that display certain characteristics.

• Public versus private institutions. Data from the National Center for Education Statistics (NCES) show that students who enrolled at public four-year institutions in 1995-1996 were less likely than peers at private, not-for-profit institutions to earn a bachelor’s degree at their first institutions (50 percent versus 65 percent). Counting students who earned a degree at another institution, the rates were 61 percent and 76 percent, respectively.
• Two-year versus four-year colleges. Students who start out at a two-year college with plans to move on to a four-year college for a bachelor’s degree face an uphill battle. Patrick Terenzini, a senior scientist and professor of higher education at Pennsylvania State University, estimates that beginning pursuit of a bachelor’s degree at a two-year rather than a four-year institution reduces one’s chances of ultimately earning a four-year degree by 15 to 20 percentage points.
• Concentrations of low-income students. Research conducted by M. Lee Upcraft and Jennifer L.Crissman have shown that institutions with high concentrations of low-income students have lower graduation rates than institutions with lower concentrations of such students.
• Local factors. Dropout rates also are affected by idiosyncrasies of particular institutions. “Retention has a local address,” said Richard Miller of Noel-Levitz, citing two examples: “You are vulnerable if you have lousy study habits and go to a (rigorous) college ... or if you are an agnostic attending a Christian institution.”