Simultaneous Inferences for Ratio Parameters Using Multiple Contrasts Test

  • Dan LinEmail author
  • Gemechis D. Djira
  • Ziv Shkedy
  • Tomasz Burzykowski
  • Ludwig A. Hothorn
Part of the Use R! book series (USE R)


In Chap. 16, we wish to search for genes for which the mean gene-expression increases by 100 ×δ% from the control for at least one (perhaps the highest) dose, where δ is a relative biological ratio of interest. Genes can be tested for a pre-specified δ and can be ranked based on the significance of the ratio test. Genes found significant with a large δ are of higher interest to the biologists. We discuss the ratio test statistic and the link between Williams- and Marcus-type multiple contrasts tests (MCTs) and the corresponding ratio testing procedures


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Dan Lin
    • 1
    Email author
  • Gemechis D. Djira
    • 3
  • Ziv Shkedy
    • 2
  • Tomasz Burzykowski
    • 2
  • Ludwig A. Hothorn
    • 4
  1. 1.Veterinary Medicine Research and DevelopmentPfizer Animal HealthZaventemBelgium
  2. 2.Interuniversity Institute for Biostatistics and Statistical Bioinformatics (I-BioStat), Center for Statistics (CenStat)Hasselt UniversityDiepenbeekBelgium
  3. 3.Department of Mathematics and StatisticsSouth Dakota State UniversityBrookingsUSA
  4. 4.Institute of BiostatisticsLeibniz University HannoverHannoverGermany

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