Instead of generating a term by document matrix, where each term is tfidf (product of term frequency and inverse document frequency), we compute a term by document matrix MD ∈ ℜ m×l , where each term in the matrix is That is, the product of the projection of a word onto a target VNC and inverse document frequency.
the term frequency (tf) of a word is replaced by the projection of the word onto σvn (1).