Abstract
In this paper, we discuss effectiveness of “relative expressions” for trend information extraction. Relative expressions, for example, “12% increase”, “last year”, “the first place” and so forth, show relative difference and variation of numerical value implicitly. To extract more trend information from newspaper articles, one of possible means would be to utilize relative expressions. We investigated functions and statistical trend of the relative expressions in newspaper articles. And rules to extract basic elements were generated for trend information extraction. To evaluate effectiveness of the extraction rules, we experimented on newspaper articles. The result shows 0.8 or more F-measure. It was confirmed that relative expression-based extraction should well-performed.
