1. A computerized method of representing multidimensional data, comprising the steps of: a) partitioning the multidimensional data into one or more clusters; b) generating and storing clustering information for said one or more clusters; c) generating one or more reduced dimensionality clusters and dimensionality reduction information for said one or more clusters; d) storing the dimensionality reduction information; e) creating a hierarchy of reduced dimensionality clusters by recursively applying said steps a) through d); and f) generating and storing one or more low-dimensional idexes for clusters at a lowest level of said hierarchy.