This article presents evidence strengthening the argument against comparison group strategies
given the current state of knowledge. The comparison group for this study was drawn explicitly
recognizing the self-selection issues. It drew youths from similar sources matched on attitudes
related to California Conservation Corps (CCC) participation not usually measured and
collected information explicitly designed to improve the statistical modeling of participation.
Yet, as always, whether a comparison group strategy works is an empirical question. One
believes the results from such a study only if they basically conform to one's prior beliefs,
otherwise the suitability of a comparison group is suspect.
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