What documentation exists for R?

Chapter 5: R Add-On Packages 53
pls Partial Least Squares Regression (PLSR) and Principal Component Regression
(PCR).
plsgenomics
PLS analyses for genomics.
pmg Poor Man’s GUI.
poLCA POlytomous variable Latent Class Analysis.
polspline Routines for the polynomial spline fitting routines hazard regression, hazard
estimation with flexible tails, logspline, lspec, polyclass, and polymars, by C.
Kooperberg and co-authors.
polyapost Simulating from the Polya posterior.
polycor Polychoric and polyserial correlations.
polynom A collection of functions to implement a class for univariate polynomial manipulations.
popgen Statistical and POPulation GENetics.
portfolio Classes for analyzing and implementing portfolios.
portfolioSim
Framework for simulating equity portfolio strategies.
powell Optimizes a function using Powell’s UObyQA algorithm.
powerpkg Power analyses for the affected sib pair and the TDT design.
ppc Sample classification of protein mass spectra by peak probabilty contrasts.
pps Functions to select samples using PPS (probability proportional to size) sampling,
for stratified simple random sampling, and to compute joint inclusion
probabilities for Sampford’s method of PPS sampling.
prabclus Distance based parametric bootstrap tests for clustering, mainly thought for
presence-absence data (clustering of species distribution maps). Jaccard and
Kulczynski distance measures, clustering of MDS scores, and nearest neighbor
based noise detection.
prettyR Pretty descriptive stats.
princurve Fits a principal curve to a matrix of points in arbitrary dimension.
proptest Tests of the proportional hazards assumption in the Cox model.
proto An object oriented system using prototype or object-based (rather than classbased)
object oriented ideas.
pscl R in the Political Science Computational Laboratory, Stanford University.
pspline Smoothing splines with penalties on order m derivatives.
psy Various procedures used in psychometry: Kappa, ICC, Cronbach alpha,
screeplot, PCA and related methods.