Simple random sample

In statistics, a simple random sample from a population is a sample chosen randomly, in which each member of the population has the same probability of being chosen. In small populations such sampling is typically done "without replacement", i.e., one deliberately avoids choosing any member of the population more than once.

Simple random sampling is not an efficient method since it does not consider the available information about the population. It best suits situations where the population is fairly homogeneous and not much information is available about the population. If these conditions are not true, stratified sampling may be a better choice.