8. The method of claim 7 wherein the step of ranking each of the plurality of documents based on the spoken query further includes calculating a posteriori probabilities for each term in the spoken query and using the a posteriori or probabilities as weights.
9. The method of claim 8 wherein the step of ranking each of the plurality of documents based on the spoken query further includes determining a ranking for each of the plurality of documents based on the a posteriori probabilities of each term in the spoken query.