sampling (version 2.10)

UPminimalsupport: Minimal support sampling

Description

Uses the minimal support method to select a sample of units (unequal probabilities, without replacement, fixed sample size).

Usage

UPminimalsupport(pik)

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).

Arguments

pik

vector of the inclusion probabilities.

References

Deville, J.-C., Tillé, Y. (1998), Unequal probability sampling without replacement through a splitting method, Biometrika , 85, 89-101.
Tillé, Y. (2006), Sampling Algorithms, Springer.

Examples

############
## Example 1
############
#defines the prescribed inclusion probabilities
pik=c(0.2,0.7,0.8,0.5,0.4,0.4)
#selects a sample
s=UPminimalsupport(pik)
#the sample is
which(s==1)
############
## Example 2
############
data(belgianmunicipalities)
Tot=belgianmunicipalities$Tot04
name=belgianmunicipalities$Commune
pik=inclusionprobabilities(Tot,200)
#selects a sample
s=UPminimalsupport(pik)  
#the sample is
which(s==1)
#names of the selected units
as.vector(name[s==1])