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Graphical Insight and Data Analysis for the 2,2,2 Crossover Design

  • Bill Pikounis
  • Thomas E. Bradstreet
  • Steven P. Millard
Chapter

Abstract

S-Plus code is presented for the graphical insight into, and the statistical analysis of, a two-treatment, two-period, two-treatment-sequence, or 2,2,2 crossover design. In this introductory section, we describe the 2,2,2 crossover design and its uses in the pharmaceutical industry with emphasis on food interaction studies. We also introduce a specific example and a dataset which will be used pedagogically throughout the chapter. In Section 7.2, we provide a brief introduction to data management in S-Plus demonstrating just enough manipulations to facilitate the graphical methods and data analyses which follow. Section 7.3 presents a series of graphs for the initial exploration and discovery stage of the analysis of the 2,2,2 crossover design. In Section 7.4, we perform the usual normal theory ANOVA and provide a clear and decision-oriented summary and inference plot. Section 7.5 presents several graphical tools for the “visualization of the ANOVA” and a subsequent model fit assessment, and we end with a summary in Section 7.6.

Keywords

Model Check Sequence Effect Treatment Sequence Crossover Design Data Frame 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • Bill Pikounis
    • 1
  • Thomas E. Bradstreet
    • 2
  • Steven P. Millard
    • 3
  1. 1.Merck Research LaboratoriesRahwayUSA
  2. 2.Merck Research LaboratoriesBlue BellUSA
  3. 3.Probability, Statistics & InformationSeattleUSA

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