1. A system for information clustering, said system comprising; a central processing unit (CPU) for executing parts; a data accumulation part for accumulating and clustering documents in a document repository, said documents including loosely related clusters between said documents being time sliced so as to define chunks of said documents; a vector space generation part for generating document-keyword vectors, said document-keyword vectors consisting of sparse numeral values depending on presence of keywords in said documents; a dimension reduction part for reducing dimensions of said keywords to create a dimension reduction matrix of said document-keyword matrix; a centroid vector determination part for generating a centroid vector of said cluster, said cluster being retrieved from said document-keyword vector using a principal component in a same line of said dimension reduction matrix, said centroid vectors being defined from keywords and weight of documents within said cluster; and an item repository for storing said centroid vectors together with said keywords and said weights of said centroid vector.
1. A system for information clustering, said system comprising; a central processing unit (CPU) for executing parts; a data accumulation part for accumulating and clustering documents in a document repository, said documents including loosely related clusters between said documents being time sliced so as to define chunks of said documents; a vector space generation part for generating document-keyword vectors, said document-keyword vectors consisting of sparse numeral values depending on presence of keywords in said documents; a dimension reduction part for reducing dimensions of said keywords to create a dimension reduction matrix of said document-keyword matrix; a centroid vector determination part for generating a centroid vector of said cluster, said cluster being retrieved from said document-keyword vector using a principal component in a same line of said dimension reduction matrix, said centroid vectors being defined from keywords and weight of documents within said cluster; and an item repository for storing said centroid vectors together with said keywords and said weights of said centroid vector. 3. The system of claim 1 , wherein said vector space generation part executes dimension reduction to each of said chunks of said dimension reduction matrix and said centroid vector generation part generates clusters for every chunk of said dimension reduction matrix.