Three data sampling methods: Random sampling - selecting a person to interview or site to measure, at random. Random sampling is unbiased as particular people or places are not specifically selected.

Figure 1: Sampling distributions of estimators can be used to predict the precision and accuracy of estimates of population characteristics.

In this article, we consider estimation of parameters of random effects models from samples collected via complex multistage designs. Incorporation of sampling weights is one way to reduce estimation ...