# 2. Simple Random Sampling

Published Online: 10 FEB 2012

DOI: 10.1002/9781118162934.ch2

Copyright © 2012 John Wiley & Sons, Inc.

Book Title

## Sampling, Third Edition

Additional Information

#### How to Cite

Thompson, S. K. (2012) Simple Random Sampling, in Sampling, Third Edition, John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9781118162934.ch2

#### Publication History

- Published Online: 10 FEB 2012
- Published Print: 23 FEB 2012

#### Book Series:

#### Book Series Editors:

- Walter A. Shewhart and
- Samuel S. Wilks

#### ISBN Information

Print ISBN: 9780470402313

Online ISBN: 9781118162934

- Summary
- Chapter

### Keywords:

- estimator;
- population mean;
- random sampling;
- variance

### Summary

Simple random sampling, or random sampling without replacement, is a sampling design in which *n* distinct units are selected from the *N* units in the population in such a way that every possible combination of n units is equally likely to be the sample selected. This chapter begins with a discussion of selecting a simple random sample. With simple random sampling, the sample mean is an unbiased estimator of the population mean. Also with simple random sampling, the sample variance is an unbiased estimator of the finite-population variance. The chapter then discusses random sampling with replacement. It presents derivations for random sampling and describes model-based approach to sampling. The chapter finally illustrates simple computations for sampling using the open-source statistical programming language R.

#### Controlled Vocabulary Terms

estimator; mean; random sampling; variance