NCJ Number
118244
Date Published
1979
Length
29 pages
Annotation
This chapter explains the characteristics required of a psychological instrument that will predict delinquency and examines current problems in the development of such an instrument.
Abstract
To demonstrate the effectiveness of a psychological instrument, certain properties of the instrument and of the behavior it is to gauge must be estimated from actual data. Any index of delinquency potential is a possible predictor of behavior, and the behavior in turn constitutes a criterion. To the extent that scores on the predictor relate to scores on the criterion, the predictor is valid. When criterion scores clearly describe or represent the offense behavior, the criterion is valid. To be valid, both predictor and criterion must be reliable, which occurs if scores are relatively unchanged when people are measured a second time after a suitable time lapse. The base rate of the criterion categories is critical in the practical use of a predictor. Given a valid predictor, the more selective one is about which persons to test, the more certain one can be that they have a high potential for delinquency. Unsatisfactory criteria and unfavorable base rates and selection ratios remain major obstacles to progress in predicting delinquency and delinquency recidivism. 76 references.