UPrandomsystematic {sampling}

Random systematic sampling

Description

Selects a sample using the systematic method, when the order of the population units is random (unequal probabilities, without replacement, fixed sample size).

Usage

UPrandomsystematic(pik,eps=1e-6)

Arguments

pik

vector of the inclusion probabilities.

eps

control value, by default equal to 1e-6.

Value

Returns a vector (with elements 0 and 1) of size N, the population size. Each element k of this vector indicates the status of unit k (1, unit k is selected in the sample; 0, otherwise). The value 'eps' is used to control pik (pik>eps and pik<1-eps).

References

Madow, W.G. (1949), On the theory of systematic sampling, II, Annals of Mathematical Statistics, 20, 333-354.

See Also

UPsystematic

Examples

#define the prescribed inclusion probabilities
pik=c(0.2,0.7,0.8,0.5,0.4,0.4)
#select a sample
s=UPrandomsystematic(pik)
#the sample is
(1:length(pik))[s==1]