Temporal Query Processing with Indeenite Information

Time is an important aspect of information in medical domains. In this paper, we adopt Allen's innuential interval algebra framework for representing temporal information. The interval algebra allows the representation of indeenite and incomplete information which is necessary in many applications. However, answering interesting queries in this framework has been shown to be almost assuredly intractable. We show that when the representation language is suuciently restricted we can develop eecient algorithms for answering interesting classes of queries including: (i) determining whether a formula involving temporal relations between events is possibly true and necessarily true; and (ii) answering aggregation questions where the set of all events that satisfy a formula are retrieved. We also show, by examining applications of the interval algebra discussed in the literature, that our restriction on the representation language often is not overly restrictive in practice.