A computer-implemented system and method is disclosed for retrieving documents
using context-dependant probabilistic modeling of words and documents. The present
invention uses multiple overlapping vectors to represent each document. Each vector
is centered on each of the words in the document, and consists of the local environment,
i.e., the words that occur close to this word. The vectors are used to build probability
models that are used for predictions. In one aspect of the invention a method of
context-dependant probabilistic modeling of documents is provided wherein the text
of one or more documents are input into the system, each document including human
readable words. Context windows are then created around each word in each document.
A statistical evaluation of the characteristics of each window is then generated,
where the results of the statistical evaluation are not a function of the order
of the appearance of words within each window. The statistical evaluation includes
the counting of the occurrences of particular words and particular documents and
the tabulation of the totals of the counts. The results of the statistical evaluation
for each window are then combined. These results are then used for retrieving a
document, for extracting features from a document, or for finding a word within
a document based on its resulting statistics.
