1. A method of generating a language model from a corpus of directory assistance listings, the language model used to estimate a desired directory assistance listing based on a listing request input, the method comprising: for each word in each listing in the corpus, generating, using a processing unit, language model counts attributable to the word by: generating the language model counts attributable to the word based on whether the word is likely to be omitted from the listing request input when the desired directory assistance listing is a listing that contains the word; generating the language model counts attributable to the word based on a characteristic indicative of how well the word operates to distinguish the listing that contains the word from other listings in the corpus; and storing the language model with the language model counts.