This example illustrates how you can use PROC SURVEYMEANS to estimate population means and proportions from sample survey data. The study population is a junior high school with a total of 4,000 ...

The example in the section "Stratified Sampling" assumes that the sample of students was selected using a stratified simple random sampling design. This example shows analysis based on a more complex ...

A statistically designed random sampling scheme, based on as few as 100 people, would give a very high probability of detecting if there are any COVID-19 cases and highlight at-risk hotspots.