Language modeling for what-with-where on GOOG-411

This paper describes the language modeling architectures and recognition experiments that enabled support of ’what-withwhere’ queries on GOOG-411. First we compare accuracy trade-offs between a single national business LM for business queries and using many small models adapted for particular cities. Experimental evaluations show that both approaches lead to comparable overall accuracy. Differences in the distributions of errors also lead to improvements from a simple combination. We then optimize variants of the national business LM in the context of combined business and location queries from the web, and finally evaluate these models on a recognition test from the recently fielded ’what-with-where’ system. Index Terms: Language modeling, directory assistance, voice search, speech recognition