Stratified Sampling
Definition of Stratified Sampling
Stratified sampling is a method of probability sampling such that subpopulations within an overall population are identified and included in the sample selected in a balanced way.
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Examples of Stratified Sampling in the following topics:

Sampling Techniques
 As long as the starting point is randomized, systematic sampling is a type of probability sampling.
 Stratified Sampling Where the population embraces many distinct categories, the frame can be organized by these categories into separate "strata."
 Stratified sampling can increase the cost and complicate the research design.
 Quota Sampling In quota sampling, the population is first segmented into mutually exclusive subgroups, just as in stratified sampling.
 Accidental Sampling Accidental sampling (or grab, convenience, or opportunity sampling) is a type of nonprobability sampling which involves the sample being drawn from that part of the population which is close to hand.
 Sampling is concerned with choosing a subset of individuals from a statistical population to estimate characteristics of a whole population.

Conducting Polls
 Stratified sampling is a method of probability sampling such that subpopulations within an overall population are identified and included in the sample.