We are assuming a new document corpus considering each term/keyword as independent. Our aim is to reduce the number of dimensions of such a corpus.
What SVD does?
Given a matrix M find a matrix M` which has less number of dimensions that M. (rank of M` < rank of M)
Rank of a matrix = Size of the largest sub-matrix which has a non-zero determinant. (Rank of M can be considered as "true" dimensionality)
--Shreejay
