Conceptual and Quantitative Representations of Time Expressions
Shoji Mizobuchi, Kazuhiro Morita, Masao Fuketa, Jun‐ichi Aoe · International Journal of Computer Processing Of Languages · 2000
In natural language processing systems, it is very important to understand the meaning of time expressions and convert them into formal representations which include quantitative values. This paper proposes a method for understanding time expressions. For components of which time expressions consist, 31 concepts are introduced. Formal representations for these concepts are defined and an algorithm of analyzing the meaning of time expressions is proposed. The representation includes both conceptual and quantitative aspects in comparison with traditional approaches such as those of machine translation systems, and allows for more precise understanding of time expressions. An algorithm for translating time expressions into the corresponding formal representation by using a left-to-right parsing technique is presented. Experiments for about 2,000 time expressions extracted from actual documents show that the proposed method yields correct interpretation in about 93% of the cases.