Difference between revisions of "Semantic Affinity"

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Semantic Affinity of a linguistic-pattern is a measure for judging the effectiveness of that pattern in extracting the required Noun-Phrases belonging to a semantic class. The term was first used by Patwardhan and Riloff in their [[Learning Domain-Specific Information Extraction Patterns from the Web|paper]] on learning domain-specific IE patterns from the web.
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Semantic Affinity of a linguistic-pattern is a measure for judging the effectiveness of that pattern in extracting the required Noun-Phrases belonging to a semantic class. The term was first used by Patwardhan and Riloff in their [[Learning Domain-Specific Information Extraction Patterns from the Web|paper]] on learning domain-specific IE patterns from the web.<br>
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Mathematically semantic affinity for a pattern is defined as:<br>
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<math>affinity{_p}{_a}{_t}{_t}{_e}{_r}{_n}=f{_c}{_l}{_a}{_s}{_s}/f{_a}{_l}{_l} \cdot log{_2}f{_c}{_l}{_a}{_s}{_s}</math><br>
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where <math>f{_c}{_l}{_a}{_s}{_s}</math> is the frequency of occurrence of the pattern where it had a noun-phrase from the semantic class "class", and <math>f{_a}{_l}{_l}</math> is the total frequency of occurrence of that pattern in the corpus.

Revision as of 18:03, 3 October 2011

Semantic Affinity of a linguistic-pattern is a measure for judging the effectiveness of that pattern in extracting the required Noun-Phrases belonging to a semantic class. The term was first used by Patwardhan and Riloff in their paper on learning domain-specific IE patterns from the web.
Mathematically semantic affinity for a pattern is defined as:


where is the frequency of occurrence of the pattern where it had a noun-phrase from the semantic class "class", and is the total frequency of occurrence of that pattern in the corpus.