More than 70 percent of colleges in the U.S. use placement tests to determine which students are required to take remedial courses. However, a working paper recently published by the National Bureau of Economic Research suggests that an algorithm may be a more effective way of making this determination. The algorithm, which was tested on more than 12,500 students at seven community colleges over a two-year period, placed fewer students in remedial courses while also showing an improved rate of performance among students place in college-level rather than remedial English and math courses.