An approach to measuring rotatability in central composite designs

  • Authors

    • Emmanuel Ohaegbulem Department of Statistics,Imo State University, Owerri
    • Polycarp Chigbu Department of Statistics, University of Nigeria, Nsukka, Enugu State.
    2015-05-31
    https://doi.org/10.14419/ijasp.v3i2.4657
  • Central Composite Designs, Design Rotatability, Near Rotatable Designs, Perfectly Rotatable Designs, Second-Order Response-Surface Designs.

  • An approach to measure design rotatability and a measure, that quantifies the percentage of rotatability (from 0 to 100) in the central composite designs are introduced. This new approach is quite different from the ones provided by previous authors which assessed design rotatability by the viewing of tediously obtained contour diagrams. This new approach has not practical limitations, and the measure is very easy to compute. Some examples were used to express this approach.

  • References

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