In 1930, Duke University became the second major U.S. academic institution to engage in the critical study of ESP and psychokinesis in the laboratory. Under the guidance of psychologist William McDougall, and with the help of others in the department—including psychologists Karl Zener, Joseph B. Rhine, and Louisa E. Rhine—laboratory ESP experiments using volunteer subjects from the undergraduate student body began. As opposed to the approaches of psychical research, which generally sought qualitative evidence for paranormal phenomena, the experiments at Duke University proffered a quantitative, statistical approach using cards and dice. As a consequence of the ESP experiments at Duke, standard laboratory procedures for the testing of ESP developed and came to be adopted by interested researchers throughout the world.