Báo cáo khoa học: "Evaluation of Importance of Sentences based on Connectivity to Title" doc

Evaluation of Importance of Sentences
based on Connectivity to Title
Takehiko Yoshimi and Toshiyuki Okunishi
Takahiro Yamaji and Yoji Fukumochi
Software Business Development Center, SHARP Corporation
492 Minosho-cho Yamatokoriyama Nara, Japan
Abstract
This paper proposes a method of selecting impor-
tant sentences from a text based on the evaluation
of the connectivity between sentences by using sur-
face information. We assume that the title of a text
is the most concise statement which expresses the
most essential information of the text, and that the
closer a sentence relates to an important sentence,
the more important this sentence is. The importance
of a sentence is defined as the connectivity between
the sentence and the title. The connectivity between
two sentences is measured based on correference be-
tween a pronoun and a preceding (pro)noun, and on
lexical cohesion of lexical items. In an experiment
with 80 English texts, which consist of an average
of 29.0 sentences, the proposed method has marked
recall of 78.2% and precision of 57.7%, with the se-
lection ratio being 25%. The recall and precision
values surpass those achieved by conventional meth-
ods, which means that our method is more effective
in abridging relatively short texts.
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