Opinion Sentence Search
Engine on Open-domain Blog
Osamu Furuse, Nobuaki Hiroshima,
Setsuo Yamada, Ryoji Kataoka
NTT Cyber Solutions Laboratories,
NTT Corporation
IJCAI 2007
Reporter: Chia-Ying Lee
Advisor: Hsin-Hsi Chen
Introduction
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A user want to know others’ opinion
about a product or something
Input: query phrase
Output: relevant opinion sentence
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Explicitly stated opinion sentence
Exclude quoted or implicational opinions
Including positive, negative and neutral
Opinion clues
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Opinion Sentences to be Searched
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Opinion clues [Hiroshima et al. 2006]
1. Evaluative adjectives placed in the
predicate part
This house is beautiful.
2. Subjective sentential adverbs(全句副詞)
Amazingly, few people came to my party.
3. Idiomatic collocations (慣用語搭配) in
main clause
My wish is to go abroad.
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Architecture of Opinion Sentence Search(1/3)
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Architecture of Opinion Sentence
Search(2/3)
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High proportion off-line processing
Presented in a blog page unit
Ranked according to
 The number
 The ratio
 Total strength
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Architecture of Opinion Sentence Search(3/3)
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Opinion Sentence Extraction(1/4)
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Opinion clue expression collection
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Top 20 web pages with 40 queries
13,363 opinion sentences judged by all 3
evaluator
2,936 opinion clues judged by human
Japanese predicates are in principle
placed in the last part of a sentence.
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2,514 clues in predicates ; 422 not in.
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Opinion Sentence Extraction(3/4)
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Augmentation by semantic categories
Opinion clue expressions and cooccurring words
(X) The sky is high.
(O) The quality of this product is high.
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Opinion Sentence Extraction(4/4)
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Binary classifies sentences using SVM
Features:
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2,936 opinion clue expressions
2,715 semantic categories
150 frequent words
13 parts of speech
Number
Train set Test set
Query
72
18
Total sentence
23,800
5,686
Sentence at least one judged opinions
8,050
1,791
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Query-relevant Sentence Extraction
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Accepting weak query relevance
Strategies about query relevant
(a) A query phrase occurs in the sentence or
within some number of sentences before the
sentence.
(b) A query phrase occurs in the sentence or
within the chunk opinion sentences
consecutively appear in.
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Experiment ─
Opinion Sentence Extraction(1/2)
Baseline: Regards a sentence contain more
than 4 opinion clues as a opinion sentence
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Experiment ─
Opinion Sentence Extraction(2/2)
Quasi predicate part: Features are permitted
only within the last ten words in the sentence
Recall: 74.3 % to 3 judged
62.0 % to 2 judged
44.4 % to 1 judged
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Experiment ─ Query Relevance
Baseline: A query phrase occurs in the
sentence
Data set: 2,868 opinion sentences
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Experiment ─ total performance
Data set: 429 query-relevant opinion
sentence out of 5,686 sentences (7.5%)
Opinion sentences tend to be more query-relevant
than non-opinion sentences.
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Conclusion and Future Work
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The experiments suggested that the
system is a practical application
Improve query-relevant strategy
Classify opinion sentences in terms of
emotion, sentiment, requirement, and
suggestion
Summarize
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 Thank You! 
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