Sample

A sample is a subset of the entire population. In inferential statistics, the goal is to use the sample to learn about the population. Consequently, the sample typically is selected in a manner that allows it to be an unbiased representation of the entire population. Drawing a random sample is a common method for achieving this unbiased representation. In a simple random sample, each member of the population has an equal probability of being included in the sample. However, different modifications of simple random samples can be used to meet specific research needs.