4. Sample Size

  1. Steven K. Thompson

Published Online: 10 FEB 2012

DOI: 10.1002/9781118162934.ch4

Sampling, Third Edition

Sampling, Third Edition

How to Cite

Thompson, S. K. (2012) Sample Size, in Sampling, Third Edition, John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9781118162934.ch4

Author Information

  1. Simon Fraser University, Canada

Publication History

  1. Published Online: 10 FEB 2012
  2. Published Print: 23 FEB 2012

Book Series:

  1. Wiley Series in Probability and Statistics

Book Series Editors:

  1. Walter A. Shewhart and
  2. Samuel S. Wilks

ISBN Information

Print ISBN: 9780470402313

Online ISBN: 9781118162934



  • population mean;
  • random sampling;
  • relative precision;
  • sample size


This chapter first discusses sample size for estimating a population mean. With simple random sampling, the sample mean is an unbiased estimator of the population mean. The chapter then describes estimation of a population total using sample size. A bothersome aspect of sample size formulas is that they depend on the population variance, which generally is unknown. In practice, one may be able to estimate the population variance using a sample variance from past data from the same or a similar population. Finally, the chapter discusses sample size for relative precision.

Controlled Vocabulary Terms

mean; random sampling; Sample size; variance