2. The method of claim 1 , wherein the word sequence is associated with a first linguistic item, and wherein the concept vector comprises a first concept vector, and wherein the method further comprises: performing said forming, transforming, generating, and projecting with respect to at least a second linguistic item, to produce a second concept vector; and comparing the first concept vector with the second concept vector to generate a similarity measure.
2. The method of claim 1 , wherein the word sequence is associated with a first linguistic item, and wherein the concept vector comprises a first concept vector, and wherein the method further comprises: performing said forming, transforming, generating, and projecting with respect to at least a second linguistic item, to produce a second concept vector; and comparing the first concept vector with the second concept vector to generate a similarity measure. 5. The method of claim 2 , wherein the first linguistic item corresponds to a query and the second linguistic item corresponds to an ad.