Bridgepoint Education Inc., the for-profit company that owns Ashford University, lost a third of its value after Ashford’s accreditation application was denied by the Western Association of Schools and Colleges. Ashford, with a campus in Iowa, has grown tenfold since Bridgepoint bought it in 2005 and became mainly an online university that has large numbers of dropouts. “This level of attrition is, on its face, not acceptable,” the association said. “Serious concerns” also exist about the courses’ rigor.