At the outset of World War I, U.S. Army officials were faced with the monumental task of screening an enormous number of army recruits. In 1917, psychologist Robert Yerkes developed two tests known as the Army Alpha and Beta tests. The Army Alpha was- designed as a written test, while the Army Beta was administered orally in cases where recruits were unable to read. The tests were administered to over two million soldiers in an effort to classify recruits and to determine which of them were officer material. The results of the tests raised questions not only about the mental abilities and backgrounds of the men but also about possible biases in the tests themselves.