Skip to main content

Statistical Methods for Testing and Evaluating Defense Systems Interim Report (1995) / Chapter Skim
Currently Skimming:

Appendix B: A Short History of Experimental Design, with Commentary for Operational Testing
Pages 55-61

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 55...
... This is due largely to the increased emphasis on quality improvement and the important role played by statistical methods in general, and design of experiments in particular, in The work of the Japanese quality consultant G Taguchi on robust design for variation reduction has shown the power of experimental design techniques for quality improvement.
Read the entire page →
From page 56...
... What is required is the kind of expertise that can adapt underlying basic principles to the current situation, an expertise rarely found outside the scope of well-trained statisticians who understand the relation of standard rules to underlying principles. Both to serve as a reference point for later discussion and to help summarize the progress made in this field, we describe a few of the basic principles and tools of experimental design in barest outline.
Read the entire page →
From page 57...
... Another approach to reducing the bias is to select the allocation within the block by randomization. Often in operational testing applications with a small number of test articles, randomization may not be necessary, and small systematic designs can be used safely.
Read the entire page →
From page 58...
... For such cases, an elegant mathematical theory of incomplete block designs was developed, supplemented by a theory dealing with fractional factorial designs, latin squares, and graeco-latin squares for studying the main effects and low-order interactions in a small number of runs. These designs tend to achieve efficiency and balance while reducing potential biases, leading to relatively simple analysis.
Read the entire page →
From page 59...
... was an adequate approximation, but were somewhat concerned with the possibility that gamma was substantial, and so wanted to be highly efficient for the linear mode! with some recourse in case the quadratic model was appropriate, then minor variations from the optimal design for the linear mode]
Read the entire page →
From page 60...
... Composite designs that supplement the 2n factorial designs with additional points contribute useful information about quadratic effects. In particular, there is a useful class of rotatable designs that are efficient and easy to analyze and comprehend.
Read the entire page →
From page 61...
... Although the initial theory confined attention to experiments in which identical trials were repeated, the concept is naturally extended to sequential experimentation. Here, after each trial or experiment, the analyst-designer can decide whether to stop experimentation and make a terminal decision, or continue experimentation.
Read the entire page →

Key Terms

  • operational testing
  • factorial designs
  • response surface
  • unknown parameter
  • design techniques

  • fractional factorial
  • robust design
  • factorial design
  • optimal design
  • sequential experimentation

  • response surfaces
  • quadratic effects
  • surface designs
  • stress x
  • quality improvement

  • designs developed
  • optimal experimental
  • developmental testing
  • resulting estimates
  • orthogonal arrays

  • experimental designs
  • control settings
  • bayesian inference
  • preliminary experiment
  • linear trends

  • satisfactory results
  • underlying basic
  • designs tend
  • screening experiments
  • gaining useful


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.