The Crazy LSI man strikes again (aka derivation of the Dq= q'US^-1formula)

[Subbarao Kambhampati <rao@asu.edu>]

Enclosed for your edification is the derivation of the formula for 
converting a query in the original space to a query in the LSI space.

In doing the derivation we use the fact that the U and V matrices are 
orthonormal and that S is a diagonal matrix, plus a few little things about 
transposition operation.

Fun to look at to brush your matrix algebra..

Rao

doc3p.pdf