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IMPACT User's Guide

NCJ Number
101487
Author(s)
O Dall
Date Published
1985
Length
171 pages
Annotation
This is the user's guide for Interactive Models for Projecting Arrest and Corrections Trends (IMPACT), which is a comprehensive package of computer programs for estimating future corrections populations.
Abstract
The user's guide serves as an introduction to the theory of impact modeling, as a practical guide to various projection methods, and as a reference to the package for the experienced user. The guide provides an overview of population projections which support public policy decisions and reviews various impact programs used by the States. The user is led through the process of designing a project, addressing some general questions about IMPACT, and detailing the projection methods available in the package. The guide describes the step-by-step process for running a projection and reviews the options for displaying, comparing, and combining the projection results. Detailed descriptions for executing the projections include a display of the projection results. Two examples of how to project corrections populations using IMPACT provide an indepth understanding of the entire projection procedure. The guide also presents detailed descriptions of the mathematical algorithms used in IMPACT's projection methods. Glossary and 56-item selected bibliography.