William G. Roll, German-American psychologist and parapsychologist (b. 1926)
William G. Roll (July 3, 1926 – January 9, 2012) was an American psychologist and parapsychologist on the faculty of the Psychology Department of the University of West Georgia in Carrollton, Georgia. Roll is most notable for his belief in poltergeist activity. He coined the term "recurrent spontaneous psychokinesis" (RSPK) to explain poltergeist cases. However, RSPK was never accepted by mainstream science and skeptics have described Roll as a credulous investigator.