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Evaluating the Predictive Validity of the Compas Risk and Needs Assessment System

NCJ Number
225689
Journal
Criminal Justice and Behavior: An International Journal Volume: 36 Issue: 1 Dated: January 2009 Pages: 21-40
Author(s)
Tim Brennan; William Dieterich; Beate Ehret
Date Published
January 2009
Length
20 pages
Annotation
This study examined the statistical validation of Correctional Offender Management Profiling for Alternative Sanctions (COMPAS), a recently developed, fourth-generation risk-need assessment system.
Abstract
Results of a first general conclusion showed that a majority of these scales reached levels of internal consistency and predictive validity that were within generally acceptable ranges. Second, the separate univariable analyses showed that a majority of the specific COMPAS risk and need base scales were significantly associated with felony recidivism. Third, results from survival analyses demonstrated that the predictive power of the three models tested was comparable to, and in some cases, higher than similar risk predictive instruments in the field. The results are encouraging and suggest that the COMPAS risk models reach levels of reliability, predictive validity, and generalizability that are at least equal to those of other major instruments in offender risk assessment. Given that instrument validation is an ongoing process, numerous further tests and models could be applied to examine the predictive validity of COMPAS risk models. Data were collected from 2,328 participants who were assessed with COMPAS as part of their processing at entry into probation agencies. Tables, figure, references, and appendix