- Latent Semantic Analysis http://cran.r-project.org/web/packages/lsa/index.html
The basic idea of latent semantic analysis (LSA) is, that text do have a higher order (=latent semantic) structure which, however, is obscured by word usage (e.g. through the use of synonyms or polysemy). By using conceptual indices that are derived statistically via a truncated singular value decomposition (a two-mode factor analysis) over a given document-term matrix, this variability problem can be overcome.
- R/Weka interface http://cran.r-project.org/web/packages/RWeka/index.html
An R interface to Weka (Version 3.7.1). Weka is a collection of machine learning algorithms for data mining tasks written in Java, containing tools for data pre-processing, classification, regression, clustering, association rules, and visualization. Both the R interface and Weka itself are contained in the RWeka package. For more information on Weka see http://www.cs.waikato.ac.nz/~ml/weka/.
- Snowball Stemmers http://cran.r-project.org/web/packages/Snowball/
- Text Mining Package http://cran.r-project.org/web/packages/tm/index.html
A framework for text mining applications within R.