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

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 senten

E v a l u a t i o n o f I m p o r t a n c e o f S e n t e n c e s

b a s e d on C o n n e c t i v i t y to T i t l e

T a k e h i k o Y o s h i m i a n d T o s h i y u k i O k u n i s h i

T a k a h i r o Y a m a j i a n d Y o j i F u k u m o c h i

S o f t w a r e B u s i n e s s D e v e l o p m e n t C e n t e r , S H A R P C o r p o r a t i o n

492 M i n o s h o - c h o Y a m a t o k o r i y a m a N a r a , J a p a n

A b s t r a c t 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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R e f e r e n c e s

R Brandow, K Mitze, and L F Rau 1995 Auto- matic Condensation of Electric Publications by Sentence Selection Information Processing &' Management, 31(5):675-685

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