Citation

Mossman D. Law Hum. Behav. 2008; 32(3): 279-291.

Affiliation

Department of Psychiatry, Boonshoft School of Medicine, Wright State University, East Medical Plaza, First Floor, 627 Edwin C. Moses Blvd., Dayton, OH 45408-1461, USA. douglas.mossman@wright.edu

Copyright

(Copyright © 2008, American Psychological Association)

DOI

10.1007/s10979-007-9123-7

PMID

18060487

Abstract

In a recent article, Vrieze and Grove (Law Hum Behav, doi: 10.1007/s10979-007-9092-x , 2007) argue that, because of low recidivism base rates and limited predictive accuracy, an actuarial risk assessment instrument (ARAI) may produce decisions about sex offenders that are worse than simply predicting that no one will commit another sex offense. This article examines: (1) the construction and potential overfitting of ARAIs; (2) the meaning, value, and limitations of ROC areas; and (3) the relationship between the operating point that maximizes an ARAI's correct classifications and the legal criterion-"likely to reoffend"-used for sex offender designations. Contrary to what Vrieze and Grove suggest, ARAIs of modest accuracy yield probabilistic information that is more relevant to legal decision-making than just "betting the base rate."

Language: en