lcubeflightphase: Flight phase for the local cube method

In BalancedSampling: Balanced and Spatially Balanced Sampling

Flight phase for the local cube method

Description

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.

Usage

lcubeflightphase(prob,Xspread,Xbal)	

Arguments

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

Value

Returns a vector of length N with new probabilities, where at most r are non-integer.

References

Grafström, A. and Tillé, Y. (2013). Doubly balanced spatial sampling with spreading and restitution of auxiliary totals. Environmetrics, 24(2), 120-131.

Examples

## 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)

BalancedSampling documentation built on June 29, 2022, 5:06 p.m.