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Title: Problems with a Type of Matched Subjects Design and Analysis

Source: In: Proceedings of the 2015 American Statistical Association Joint Statistical Meetings, Section on Physical and Engineering Sciences, pages 3491-3505

Author(s)Verrill, Steve P.; Kretschmann, David E.

Publication Year: 2015  View PDF »

Category: Conference Proceedings
Associated Research Project(s):   FPL-4714-2B  FPL-4851-2B

Abstract: There is a type of blocked experiment that has the potential of being poorly designed and/or analyzed. Verrill et al. (1993, 1999, 2004) referred to such an experiment as a “predictor sort” experiment. David and Gunnink (1997) spoke of “artificial pairing.” In text books it is sometimes referred to as a “matched pair” or “matched subjects” design. The associated design process is also sometimes described as “forming blocks via a concomitant variable.” Improperly designed and/or analyzed, predictor sort experiments can be associated with incorrect/inadequate power calculations and sample sizes, incorrect tests of hypotheses, and incorrect confidence intervals. In this paper we review some of the results in the literature, add a section on multiple comparisons, and present results from power and confidence interval coverage simulations that emphasize the importance of the proper design and analysis of predictor sort experiments.

Keywords: Predictor sort sampling, artificial pairing, matched pairs, matched subjects, concomitant variable, blocked ANOVA, analysis of covariance

Publication Review Process: Non-Refereed (Other)

File size: 354 kb(s)

Date posted: 09/08/2016
RITS Product ID: 80997
Current FPL Scientists associated with this product (listed alphabetically)
Kretschmann, David E.
Research General Engineer
Verrill, Steve P.
Mathematical Statistician

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