In particular, two-dimensional extensions of known approximate variance estimators used in linear systematic sampling are introduced. These almost new variance estimators have the advantage of taking ...

Systematic sampling is very convenient in many practical situations, but does not provide a satisfactory estimator of the variance of the sample mean except when additional assumptions are made. A ...

PPS Systematic Sampling 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 ...

Most sampling is random, but systematic sampling can be used if there is a trend or pattern across the habitat, such as distance up a beach, or altitude on a hillside.