The method of systematic random sampling (METHOD=SYS) selects units at a fixed interval throughout the sampling frame or stratum after a random start. PROC SURVEYSELECT chooses the first unit randomly ...

If you specify the option METHOD=PPS_SYS, PROC SURVEYSELECT selects units by systematic random sampling with probability proportional to size. Systematic sampling selects units at a fixed interval ...

Systematic sampling means testing a hypothesis by taking several equally spaced items from a larger list, eg selecting the tenth, 20th and 30th visitor to a theme park. This can be particularly useful ...

Random sampling is a random means of gathering data points from all groups. It eliminates bias within your data sets by using randomness to gather points. True random sampling gives a better ...