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New Paths in Corrections Evaluations - Controlling Disruptive Variables in Time-Series Designs

NCJ Number
89974
Author(s)
W Blass-Wilhelms
Date Published
1981
Length
26 pages
Annotation
Noting that unmeasured factors are always present in social science experiments and that they constitute an initial difference between control and experimental groups which may ultimately distort the changes being measured over time, this article discusses methods for mitigating such distortive effects.
Abstract
It examines the extent to which controls against disruptive variables have been implemented in West German evaluation studies of correctional programs to ensure both the internal and external validity of the experimental results. Arguments are presented for specifying such controls into the evaluation methodology early in the planning stages, since interpretations of correctional evaluations frequently overlook this methodological requirement for political reasons. Models for the implementation of true experimental designs are then presented and consequences of their application to corrections evaluation are discussed. Over 50 references are given.