These domains also provide an ideal proving ground for a referential semantic language model, because directives in these domains mostly refer to a world model that is shared by the user and the interfaced application, and because the idiosyncratic language used in such domains makes it more resistant to domain-independent corpus training than other domains.
domains such as database query (e.g., of airline reservations), dictation, or information extraction are less likely to benefit from a referential semantic language model, because the world model in such domains is not shared by either the speaker (in database query) or by the interfaced application (in dictation or information extraction), 7 or because these domains are relatively fixed, so the expense of maintaining linguistic training corpora in these domains can often be justified.