10. A computer program product for comparing a unit of streaming text data to an existing document collection in real-time, including a computer-readable medium encoded with instructions configured to be executed by a processor in order to perform predetermined operations comprising: constructing a term-by-document matrix of the existing document collection; decomposing the term-by-document matrix into a term basis matrix, a weights matrix, and a document basis matrix; determining a multidimensional term subspace of the term basis matrix; computing a vector representation of the unit of streaming text data in real-time; transforming the vector representation into a projection into the predetermined multidimensional term subspace in real-time; calculating a relationship value indicative of the relationship between the vector representation and the predetermined multidimensional term subspace in real-time, wherein the relationship value is a residual vector that quantifies the difference between the vector representation of the streaming text data document and the subspace representing the original document collection; and appending the projection of the unit of streaming text data to the existing document collection represented by the predetermined multidimensional term subspace, the existing document collection being represented by a quantity of vectors corresponding to an equivalent quantity of documents in the existing document collection, the appending being performed without determining a new multidimensional term subspace and without adding additional terms not originally included in the term basis matrix, the appending being performed when it is determined that a relationship exists between the streaming text data and the predetermined multidimensional term subspace, wherein the relationship exists when the residual vector is less than a threshold.
13. The computer program product of claim 10 , wherein the relationship value is based at least in part on a distance between the projection and the vector representation.