A model of a computer program designed to illustrate interview problems in psychotherapy, and using an IBM 360/50 computer as the patient, is presented. After each patient statement, the therapist assigns a number to his response (using Dollard and Auld's scheme) and his affect. The computer assigns probabilities to the various patient responses depending on the therapist's statement and affect, and the number of patient-therapist interactions that have already taken place. Patient responses with the highest assigned probability are more likely to be selected by the computer, although other responses are possible. Using probability as a programming technique is an alternative to the branching method and is felt to be a closer approximation to a real interview and therefore a more appropriate model.
Hillman RG. The Teaching of Psychotherapy Problems by Computer. Arch Gen Psychiatry. 1971;25(4):324-329. doi:10.1001/archpsyc.1971.01750160036006