lcubeflightphase {BalancedSampling} | R Documentation |
Flight phase for the local cube method. To have a fixed sample size, include the inclusion probabilities as a balancing variable in Xbal
and make sure the inclusion probabilities sum to a positive integer. This is a simplified (optimized for speed) implementation of the flight phase of the local cube method (doubly balanced sampling). Euclidean distance is used in the Xspread
space.
lcubeflightphase(prob,Xspread,Xbal)
prob |
vector of length N with inclusion probabilities |
Xspread |
matrix of (standardized) auxiliary variables of N rows and q columns |
Xbal |
matrix of balancing auxiliary variables of N rows and r columns |
Returns a vector of length N with new probabilities, where at most r are non-integer.
Grafström, A. and Tillé, Y. (2013). Doubly balanced spatial sampling with spreading and restitution of auxiliary totals. Environmetrics, 24(2), 120-131.
## Not run: # Example 1 # Select sample set.seed(12345); N = 100; # population size n = 10; # sample size p = rep(n/N,N); # inclusion probabilities X = cbind(runif(N),runif(N)); # matrix of auxiliary variables pflight = lcubeflightphase(p,X,cbind(p,X)); # check balance colSums(X) colSums(X/p*pflight) ## End(Not run)