The Hajek estimator for a stratified design
Computes the Hájek estimator of the population total or population mean for a stratified design.
Hajekstrata(y,pik,strata,N=NULL,type=c("total","mean"),description=FALSE)y |
vector of the variable of interest; its length is equal to n, the sample size. |
pik |
vector of the first-order inclusion probabilities for the sampled units; its length is equal to n, the sample size. |
strata |
vector of size n, with elements indicating the unit stratum. |
N |
vector of population sizes of strata; N is only used for the total estimator; for the mean estimator its value is NULL. |
type |
the estimator type: total or mean. |
description |
if TRUE, the estimator is printed for each stratum; by default, FALSE. |
# Swiss municipalities data base
data(swissmunicipalities)
# the variable 'REG' has 7 categories in the population
# it is used as stratification variable
# computes the population stratum sizes
table(swissmunicipalities$REG)
# do not run
# 1 2 3 4 5 6 7
# 589 913 321 171 471 186 245
# the sample stratum sizes are given by size=c(30,20,45,15,20,11,44)
# the method is simple random sampling without replacement
# (equal probability, without replacement)
st=strata(swissmunicipalities,stratanames=c("REG"),size=c(30,20,45,15,20,11,44),
method="srswor")
# extracts the observed data
# the order of the columns is different from the order in the swsissmunicipalities database
x=getdata(swissmunicipalities, st)
# computes the population sizes of strata
N=table(swissmunicipalities$REG)
N=N[unique(x$REG)]
#the strata 1 2 3 4 5 6 7
#corresponds to REG 4 1 3 2 5 6 7
# computes the Hajek estimator of the variable Pop020
Hajekstrata(x$Pop020,x$Prob,x$Stratum,N,type="total",description=TRUE)Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.