8. The method of claim 7 wherein the step of determining a property about which the user will be queried further includes the steps of: selecting one of the properties and designating it as a first property; computing the expected number of subsequent queries given that the first property is the property the user is asked about first; repeating the selecting and computing steps for each of the remaining properties; and selecting the property that yields the minimum expected number of subsequent queries for use in the initial system query.
7. The method of claim 1 further including the step of determining a property about which the user will be queried in an initial system query, by computing an expected number of subsequent queries for each of the properties of one or more of the frames.