Journal of Statistical Theory and Practice

, Volume 7, Issue 4, pp 687–702 | Cite as

Identification of Dispersion Effects in Replicated Two-Level Fractional Factorial Experiments

  • Cheryl Dingus
  • Bruce Ankenman
  • Angela DeanEmail author
  • Fangfang Sun


Tests for dispersion effects in replicated two-level factorial experiments assuming a location-dispersion model are presented. The tests use individual measures of dispersion that remove the location effects and also provide an estimate of pure error. Empirical critical values for two such tests are given for two-level full or regular fractional factorial designs with 8, 16, 32, and 64 runs. The powers of the tests are examined under normal, exponential, and Cauchy distributed errors. Our recommended test uses dispersion measures calculated as deviations of the data values from their cell medians, and this test is illustrated via an example.


Dispersion measures Location-dispersion model Fractional factorial experiment 


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Copyright information

© Grace Scientific Publishing 2013

Authors and Affiliations

  • Cheryl Dingus
    • 1
  • Bruce Ankenman
    • 2
  • Angela Dean
    • 3
    • 4
    Email author
  • Fangfang Sun
    • 5
  1. 1.Battelle Memorial InstituteColumbusUSA
  2. 2.Department of Industrial EngineeringNorthwestern UniversityEvanstonUSA
  3. 3.Department of MathematicsUniversity of SouthamptonSouthamptonUK
  4. 4.Department of StatisticsThe Ohio State UniversityColumbusUSA
  5. 5.Department of Management Science and EngineeringHarbin Institute of TechnologyHarbin, HeilongjiangChina

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