A '''Documentdocument-term matrix''' or '''term-document matrix''' is a mathematical [[Matrix (mathematics)|matrix]] that describes the frequency of terms that occur in a collection of documents. EachIn columna correspondsdocument-term tomatrix, arows documentcorrespond to documents in the collection, and eachcolumns row correspondscorrespond to terms. In a wordterm-document matrix, rows correspond to words or termterms and columns correspond to documents. There are various schemes for determining the value that each entry in the matrix should take. One such scheme is [[tf-idf]]. They are useful in the field of [[natural language processing]].
