12. The method of claim 10 , wherein the relationship is a synonym relationship between the meaning of the words.
10. A method for selecting a subset of words from a set of word groups associated with a product in a group of products, the method comprising the steps of: collecting coreference information the coreference information indicating coreferences in single web sessions of pairs of products in the group of products, the coreference information further indicating a number of a plurality of words across the group of products, a number of occurrences of each word for both coreferenced products of each pair of products, and a number of occurrences of each word for only one coreferenced product of each pair of products; calculating a score for each of the plurality of words in the word groups, the score being based at least in part on a relationship, and the coreference information; selecting a subset of the plurality of words based on the score; performing, on a computer, a dimensionality reduction on the subset; and serving a web page from a web server, the web page including a description of a first product and a recommendation for a second product, the recommendation being based on a result from the performing step.