Using the Sample Range as a Basis for Calculating Sample Size in Power Calculations

  title={Using the Sample Range as a Basis for Calculating Sample Size in Power Calculations},
  author={R. H. Browne},
  journal={The American Statistician},
  pages={293 - 298}
  • R. H. Browne
  • Published 2001
  • Mathematics
  • The American Statistician
Lacking a sample standard deviation to use as an estimate of σ in sample size computations, consultants often divide a sample range (R) by a constant to estimate σ. To avoid underpowered studies, the estimate must have a high probability of being greater than or equal to σ. The probability of being greater than or equal to σ is estimated for R/6, R/4, and R/(standardized mean range) for various parent distributions and a range of sample sizes. Those probabilities are found to be quite low for… Expand
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