Kelly Rosinger, a post-doc at EdPolicyWorks, has research cited in new Cavalier Daily article about test-optional admissions.
Moreover, the push to become test-optional may not be entirely altruistic. A 2014 study at the University of Georgia found that schools that drop SAT/ACT requirements receive 250 more applications on average, thus giving them a larger applicant pool that can make them appear more selective. Over time, this number will likely increase. Additionally, since students with lower test scores would likely take advantage of a test-optional policy, the average test scores of applicants and admitted students will rise. Average test scores factor into the widely-read college rankings in U.S. News & World Report.