Cluster Sampling: A False Economy?
Andrew Zelin and Roger StubbsMORI
BACKGROUND AND CONTEXT
The random sample survey is a commonly used method in market research and such surveys generally are considered to provide more robust results than purposive or convenience (such as quota) samples. Simple random samples (SRS), where every member of the population has an equal or predetermined chance of selection, and the sampling is single stage, are the simplest to visualise and the level of precision of results derived from them is easy to calculate. However, SRS are almost impossible to achieve in...