Is a process to select a sample in which every unit in the population has a chance (greater than zero) of being selected in the sample, and this probability can be accurately determined. The fact that the probability can be established does not mean that it is always calculated. cThis makes it possible to produce unbiased estimates of population totals, by weighting sampled units according to their probability of selection.
Is a process to select a sample in which every unit in the population has a chance (greater than zero) of being selected in the sample, and this probability can be accurately determined. The fact that the probability can be established does not mean that it is always calculated. cThis makes it possible to produce unbiased estimates of population totals, by weighting sampled units according to their probability of selection.