LIS 601: Week3
Term Weighting: TF * IDF

Where:

w_ij = weight of Term T_j in Document D_i


tf_ij = frequency of Term T_j in Document D_i


N = number of Documents in collection


n = number of Documents where term T_j occurs at least once

Nota Bene:

Red text is the Inverse Document Frequency measure.

Derived from:

Salton, G. 1989. Automatic text processing. Chapter 9.

Page creator: J. Stephen Downie
Page created: 24 September 1997
Page updated: 25 September 1997