16. The method as recited in claim 15 , wherein the regularizing vectors of the term-topic matrix U is based on either an l 1 norm or an l 2 norm and the regularizing vectors of the topic-document matrix V is based on either an l 1 norm or an l 2 norm.
17. The topic modeling system as recited in claim 16 , wherein the regularizing vectors of the term-topic matrix U is based on an l 1 norm and the regularizing vectors of the topic-document matrix V is based on an l 2 norm.