Selects a sample using
the pivotal method, when the order of the population units is random (unequal probabilities,
without replacement, fixed sample size).
Usage
UPrandompivotal(pik,eps=1e-6)
Arguments
pik
vector of the inclusion probabilities.
eps
the 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).
#define the prescribed inclusion probabilities
pik=c(0.2,0.7,0.8,0.5,0.4,0.4)
#select a sample
s=UPrandompivotal(pik)
#the sample is
(1:length(pik))[s==1]