sampling weights

sampling weights
Weights are used in sampling to achieve proportionality. Sampling weights are the inverse of sampling fractions. When different sampling fractions have been applied to particular sub-groups within the population studied, sampling weights are used to reinstate the original importance of each group within the population. For example, survey results obtained from using sampling fractions of 1/50 and 1/2 must be multiplied by sampling weights of 50/1 and 2/1 to reinstate their correct representation in the population as a whole.