• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.526-528
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• 2003

공기빈도를 이용한 전역적 질의확장 검색에서 공기유사도를 판정하는데 이용되는 유사계수의 특성에 따른 질의확장 성능을 비교해보았다. 먼저 각 유사계수의 통계적인 특성을 말뭉치와 검색실험 문서집단을 대상으로 살펴본 결과 코사인 계수, 자카드 계수는 고빈도어 선호경향을 보이고 상호정보량과 율의 Y는 저빈도어 선호경향을 보이는 것으로 나타났다. 질의확장 검색실험에서는 고빈도어 선호경향을 가진 유사계수에 비해서 저빈도어 선호경향을 가진 유사계수률 이용할 때 더 종은 성능이 나타났다. 특히 율의 Y는 질의어의 DF가 1에 가깝게 매우 낮을 때 다른 유사계수와 달리 고빈도어를 선호함으로써 항상 저빈도어를 선호하는 상호정보량에 비해서 질의확장 검색에 유리함을 알 수가 있었다.

• Language and Information
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• v.10 no.1
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• pp.21-46
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• 2006

This study proposes a Word Sense Disambiguation (WSD) algorithm, based on concept learning with special emphasis on statistically meaningful lowest frequency words. Previous works on WSD typically make use of frequency of collocation and its probability. Such probability based WSD approaches tend to ignore the lowest frequency words which could be meaningful in the context. In this paper, we show an algorithm to extract and make use of the meaningful lowest frequency words in WSD. Learning method is adopted from the Find-Specific algorithm of Mitchell (1997), according to which the search proceeds from the specific predefined hypothetical spaces to the general ones. In our model, this algorithm is used to find contexts with the most specific classifiers and then moves to the more general ones. We build up small seed data and apply those data to the relatively large test data. Following the algorithm in Yarowsky (1995), the classified test data are exhaustively included in the seed data, thus expanding the seed data. However, this might result in lots of noise in the seed data. Thus we introduce the 'maximum a posterior hypothesis' based on the Bayes' assumption to validate the noise status of the new seed data. We use the Naive Bayes Classifier and prove that the application of Find-Specific algorithm enhances the correctness of WSD.

• Proceedings of the Korean Society for Information Management Conference
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• 2003.08a
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• pp.253-261
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• 2003

역문헌빈도 가중치는 문헌 집단에서 출현빈도가 낮을수록 색인어의 중요도가 높다는 가정에 근거하고 있다. 이 연구에서는 역문헌빈도 가중치의 가정에 의문을 제기하고, 이를 보완하는 새로운 문헌빈도 가중치 공식을 제안하였다. 제안한 가중치 공식은 저빈도어가 아닌 중간빈도어가 더 중요하다는 가정에 근거한 것으로서 역시 문헌빈도를 이용한 함수이다. 문헌빈도에 의한 가중치를 문헌의 색인어에 부여하는 경우와 질의어에 부여하는 경우로 나누어서 실험을 수행하고, 두 경우의 차이점을 논하였다.

• Korean Journal of Cognitive Science
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• v.22 no.2
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• pp.123-143
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• 2011

At what point in the process of speech production are gestures involved? According to the Lexical Retrieval Hypothesis, gestures are involved in the lexicalization in the formulating stage. According to the Information Packaging Hypothesis, gestures are involved in the conceptual planning of massages in the conceptualizing stage. We investigated these hypotheses, using the game situation in a TV program that induced the players to involve in both lexicalization and conceptualization simultaneously. The transcription of the verbal utterances was augmented with all arm and hand gestures produced by the players. Coverbal gestures were classified into two types of gestures: lexical gestures and motor gestures. As a result, concrete words elicited lexical gestures significantly more frequently than abstract words, and abstract words elicited motor gestures significantly more frequently than concrete words. The difficulty of conceptualization in concrete words was significantly correlated with the amount of lexical gestures. However, the amount of words and the word frequency were not correlated with the amount of both gestures. This result supports the Information Packaging Hypothesis. Most of all, the importance of motor gestures was inferred from the result that abstract words elicited motor gestures more frequently rather than concrete words. Motor gestures, which have been considered as unrelated to verbal production, were excluded from analysis in many gestural studies. This study revealed motor gestures seemed to be connected to the abstract conceptualization.

• Journal of the Korean Society for information Management
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• v.20 no.4 s.50
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• pp.233-248
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• 2003

The Inverse Document Frequency (IDF) weighting method is based on the hypothesis that in the document collection the lower the frequency of a term is, the more important the term is as a subject word. This well-known hypothesis is, however, somewhat questionable because some low frequency terms turn out to be insufficient subject words. This study suggests the pivoted IDF weighting method for better retrieval effectiveness, on the assumption that medium frequency terms are more important than low frequency terms. We thoroughly evaluated this method on three test collections and it showed performance improvements especially at high ranks.

• 재활복지
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• v.20 no.1
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• pp.171-188
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• 2016

The purpose of this study is to investigate effects of three conditions-words frequency, word length, and animacy-on the performance of naming in nonfluent aphasic patients. 15 nonfluent aphasic patients and 15 normal adults were participated in this study. The words consist only of concrete nouns and confrontational naming test was used. The test consisted of 40 questions and the condition of word were frequency(low-frequency/high-frequency), length(1 syllable/3 syllables) and animacy(animate/inanimate). The result of the study was as follows. First, naming was performed better with high-frequency words than with low-frequency words in both groups. Second, naming was performed better with 1 syllable words than with 3 syllable words in both groups. Third, naming performance depending on animacy did not show significant differences in both groups. These results indicate that compared to animacy of word, word frequency and length have bigger influence on the naming, and the difference by word frequency was more pronounced for nonfluent aphasic patients than for normal adults. The results of this study suggest that target word for the assessment and intervention of nonfluent aphasic patients, words frequency should be considered first in clinical setting.