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George Carcagno, Robert Applebaum, Jon Christianson, Barbara Phillips, Craig Thornton and Joanna Will
Mathematica Policy Research, Inc.
July 18, 1986
This report was prepared under contract #HHS-100-80-0157 between the U.S.
This report results from an investigation of the extent to which differential attrition from the research sample in the Channeling Demonstration might have led to biased estimates of program impact. Two analytical approaches were adopted--a heuristic approach and a statistical modeling approach.