Document vector

A document vector is simply a set of (keyword, weight) pairs, where keyword is a word or a phrase associated with the document, and weight is a numerical measure of how important keyword is for the document. Vectors are a kind of document signature (word-weight pairs) representing a document's content in a way that allows comparison between documents. It is the numerical representation of the unstructured textual content of a document.  Vectors can be used to enable clustering and refinement operations.