Proc Surveyselect

PROC SURVEYSELECT Statement

PROC SURVEYSELECT options ;

SAMPRATE=SAS-data-set
RATE=SAS-data-set
names a SAS data set that contains sampling rates for the strata. This input data set should contain all the STRATA variables, with the same type and length as in the DATA= data set. The STRATA groups should appear in the same order in the SAMPSIZE= data set as in the DATA= data set. The SAMPRATE= data set should have a variable _RATE_ that contains the sampling rate for each stratum.

Each sampling rate value must be a positive number. You can specify each value as a number between 0 and 1. Or you can specify a value in percentage form as a number between 1 and 100, and PROC SURVEYSELECT converts that number to a proportion. The procedure treats the value 1 as 100%, and not the percentage form 1%.

The SAMPRATE= option is available only for equal probability selection methods (METHOD=SRS, METHOD=URS, METHOD=SYS, and METHOD=SEQ). For systematic random sampling (METHOD=SYS), PROC SURVEYSELECT uses the inverse of the stratum sampling rate as the interval for the stratum. See the section "Systematic Random Sampling" for details. For other selection methods, PROC SURVEYSELECT converts the stratum sampling rate to the stratum sample size before selection, multiplying the rate by the number of units in the stratum and rounding up to the nearest integer.