This function performs the landing phase of the cube method using suppression of variables proposed by Chauvet and Till<U+00E9> (2006).
landingRM(X, pikstar)
matrix of auxiliary variables on which the sample must be balanced. (The matrix should be divided by the original inclusion probabilities.)
vector of updated inclusion probabilities by the flight phase. See ffphase
A vector with elements equal to 0 or 1. The value 1 indicates that the unit is selected while the value 0 is for rejected units.
Chauvet, G. and Till<U+00E9>, Y. (2006). A fast algorithm of balanced sampling. Computational Statistics, 21/1:53-62
# NOT RUN {
N <- 1000
n <- 10
p <- 4
pik <- rep(n/N,N)
X <- cbind(pik,matrix(rgamma(N*p,4,25),ncol= p))
pikstar <- ffphase(X,pik)
s <- landingRM(X/pik,pikstar)
sum(s)
t(X/pik)%*%pik
t(X/pik)%*%pikstar
t(X/pik)%*%s
# }
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