animation (version 1.1-4)

sample.cluster: Demonstration for cluster sampling...

Description

Demonstration for cluster sampling Every rectangle stands for a cluster, and the simple random sampling without replacement is performed for each cluster. All points in the clusters being sampled will be drawn out.

Usage

sample.cluster(pop=ceiling(10 * runif(10, 0.2, 1)), size=3,
    p.col=c("blue", "red"), p.cex=c(1, 3), ...)

Arguments

pop

a vector for the size of each cluster in the population.

size

the number of clusters to be drawn out.

p.col,p.cex

different colors / magnification rate to annotate the population and the sample

...

other arguments passed to rect to annotate the ``clusters''

Value

• None (invisible `NULL').

References

Cochran, W G (1977) Sampling Techniques, Wiley, ISBN 0-471-16240-X http://animation.yihui.name/samp:cluster_sampling

See Also

sample, sample.simple, sample.ratio, sample.strat, sample.system

Examples

oopt = ani.options(interval = 1, nmax = 30)
op = par(mar = rep(1, 4))
sample.cluster(col = c("bisque", "white"))
par(op)
# HTML animation page
ani.options(ani.height = 350, ani.width = 500, nmax = 30,
interval = 1, title = "Demonstration of the cluster sampling",
description = "Once a cluster is sampled, all its elements will be
chosen.")
ani.start()
par(mar = rep(1, 4), lwd = 2)
sample.cluster(col = c("bisque", "white"))
ani.stop()
ani.options(oopt)