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NCJ Number: 82373 Add to Shopping cart Find in a Library
Title: Illinois Department of Corrections - Prison Population Projections - A Review of Methods Used by State Correctional Agencies - Volume 1
Author(s): D Miller
Corporate Author: Illinois Dept of Corrections
United States of America
Project Director: J Henning
Date Published: 1981
Page Count: 108
Sponsoring Agency: Illinois Dept of Corrections
Springfield, IL 62794
National Institute of Justice/
Rockville, MD 20849
Sale Source: National Institute of Justice/
NCJRS paper reproduction
Box 6000, Dept F
Rockville, MD 20849
United States of America
Document: PDF
Type: Statistics
Language: English
Country: United States of America
Annotation: This report is based on a survey conducted of all State departments of corrections on their prison population projection methods.
Abstract: The project research staff requested directors of corrections to supply information on the projection techniques used by their departments; replies were received from 45 States and 5 other jurisdictions. Information requests focused on four issues, including methods used, projections for prison population in the near and distant future, accuracy of past projections, and use of projections. Primary prediction methods revealed by the survey are the linear regression method; multiple regression; ratio; simulation; and time-series, nonlinear models. Findings indicate that much of the current methodology is borrowed from other fields, particularly from economic and demographic forecasting. It is suggested that improved lines of communication among forecasters, policymakers, and other interested parties are necessary for improving methodologies in the future. In developing such methodologies, important considerations include defining the goals of the projection model, improving the data bases, and incorporating informal techniques into the more formal models. Any new method will require testing of assumptions and experimentation with the data before it can be used reliably. Extensive tables and figures, three appendixes of survey results, and about 40 references are provided. (Author summary modified)
Index Term(s): Correctional planning; Data analysis; Prison population prediction; Statistical analysis; Surveys
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