Nonlinear Models in Decision Making: The Diagnosis of Psychosis versus Neurosis from the MMPI

Previous studies have found no nonlinear relationships between the MMPI scales and the diagnosis of psychosis versus neurosis (the criterion). However, these studies also found evidence for nonlinear accuracy in MMPI-based judgments of the likelihood of psychosis. The current study identifies the rules underlying this nonlinear accuracy and demonstrates their validity in predicting the criterion.