转自 http://www.r-bloggers.com
Statistics and Computation
1. R Project
Replaces: SAS, SPSS
R is a free and open source statistical computing environment that holds its own against some of the most established proprietary statistical environments. R is available on all operating systems and is free for download. R also has a community driven library of add-on packages that are also freely available and cover almost any statistical, mathematical, or optimization need.
Also a great reference manual for those switching from SAS to R is SAS and R: Data Management, Statistical Analysis, and Graphics
