Jeff Rickey is a numbers guy. But three years ago, a colleague asked him about something he'd never counted: applicants who came out of nowhere. The question intrigued Mr. Rickey, dean of admissions and financial aid at Earlham College in Indiana. He found that 17 percent of the college's applicants that year had not called, taken a tour, or…

Over the past two decades, college admissions has become a prime-time preoccupation. Most people know at least something about the process, especially if they have a teenager in high school and a college guide on their coffee table. Nonetheless, widespread public misconceptions persist about admissions requirements, the selection process, and the…