tailieunhanh - Báo cáo khoa học: "An Intermediate Representation for the Interpretation of Temporal Expressions"

The interpretation of temporal expressions in text is an important constituent task for many practical natural language processing tasks, including question-answering, information extraction and text summarisation. Although temporal expressions have long been studied in the research literature, it is only more recently, with the impetus provided by exercises like the ACE Program, that attention has been directed to broad-coverage, implemented systems. In this paper, we describe our approach to intermediate semantic representations in the interpretation of temporal expressions. . | An Intermediate Representation for the Interpretation of Temporal Expressions Pawel Mazur and Robert Dale Centre for Language Technology Macquarie University NSW 2109 Sydney Australia mpawel rdale @ Abstract The interpretation of temporal expressions in text is an important constituent task for many practical natural language processing tasks including question-answering information extraction and text summarisation. Although temporal expressions have long been studied in the research literature it is only more recently with the impetus provided by exercises like the ACE Program that attention has been directed to broad-coverage implemented systems. In this paper we describe our approach to intermediate semantic representations in the interpretation of temporal expressions. 1 Introduction In this paper we are concerned with the interpretation of temporal expressions in text that is given an occurrence in a text of an expression like that marked in italics in the following example we want to determine what point in time is referred to by that expression. 1 We agreed that we would meet at 3pm on the first Tuesday in November. In this particular case we need to make use of the context of utterance to determine which November is being referred to this might be derived on the basis of the date stamp of the document containing this sentence. Then we need to compute the full time and date the expression corresponds to. If the utterance in 1 was produced say in July 2006 then we might expect the interpretation to be equivalent to the ISO-format expression 2006-11- 07T15 The derivation of such interpretation was the focus of the TERN evaluations held under the ACE program. Several teams have developed systems which attempt to interpret both simple and much more complex temporal expressions however there is very little literature that describes in any detail the approaches taken. This may be due to a perception that such expressions are relatively easy to .