matrix of auxiliary variables on which the sample must be balanced.
selection
1, for simple random sampling without replacement at each stage,
2, for self-weighting two-stage selection.
m
number of primary sampling units to be selected.
n
number of second-stage sampling units to be selected.
PU
vector of integers that defines the primary sampling units.
comment
a comment is written during the execution if comment is TRUE.
method
the used method in the function samplecube.
Value
The function returns a matrix whose columns are the following five vectors:
the selected second-stage sampling units (0 - unselected, 1 - selected),
the final inclusion probabilities,
the selected primary sampling units,
the inclusion probabilities of the first stage,
the inclusion probabilities of the second stage.
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## Example 1
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# definition of the primary units (3 primary units)
PU=c(1,1,1,1,1,2,2,2,2,2,3,3,3,3,3)
# matrix of balancing variables
X=cbind(c(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15))
# selection of 2 primary sampling units and 4 second-stage sampling units
s=balancedtwostage(X,1,2,4,PU,comment=TRUE)
# the sample and the inclusion probabilities
s
############
## Example 2
############
data(MU284)
X=cbind(MU284$P75,MU284$CS82,MU284$SS82,MU284$ME84)
N=dim(X)[1]
PU=MU284$CL
m=20
n=60
res=balancedtwostage(X,1,m,n,PU,TRUE)
# the sample and the inclusion probabilities
res