The problem of estimating the variance of the ratio estimator in sampling with probability proportional to aggregate size is investigated. The form of nonnegative unbiased variance estimators is found ...

Sampling is a tool researchers use for marketing, sociology or empirical study. In order for sampling to be productive, the data analysis must not be tainted. There are techniques for creating a ...

A family of sampling schemes with inclusion probability proportional to size is proposed. The schemes are based upon certain combinatorial properties of balanced incomplete block designs and are ...

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 ...

If you specify the option METHOD=PPS, PROC SURVEYSELECT selects units with probability proportional to size and without replacement. The selection probability for unit i in stratum h equals n h Z hi .