Summary statistics, two-sample tests, rank tests, generalised linear models,
cumulative link models, Cox models, loglinear models, and general maximum
pseudolikelihood estimation for multistage stratified, cluster-sampled,
unequally weighted survey samples. Variances by Taylor series linearisation
or replicate weights. Post-stratification, calibration, and raking. Two-phase
subsampling designs. Graphics. PPS sampling without replacement. Principal
components, factor analysis.

WWW: http://r-survey.r-forge.r-project.org/survey/