• Title/Summary/Keyword: similarity coefficient

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On the Study of Perfect Coverage for Recommender System

  • Lee, Hee-Choon;Lee, Seok-Jun
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.4
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    • pp.1151-1160
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    • 2006
  • The similarity weight, the pearson's correlation coefficient, which is used in the recommender system has a weak point that it cannot predict all of the prediction value. The similarity weight, the vector similarity, has a weak point of the high MAE although the prediction coverage using the vector similarity is higher than that using the pearson's correlation coefficient. The purpose of this study is to suggest how to raise the prediction coverage. Also, the MAE using the suggested method in this study was compared both with the MAE using the pearson's correlation coefficient and with the MAE using the vector similarity, so was the prediction coverage. As a result, it was found that the low of the MAE in the case of using the suggested method was higher than that using the pearson's correlation coefficient. However, it was also shown that it was lower than that using the vector similarity. In terms of the prediction coverage, when the suggested method was compared with two similarity weights as I mentioned above, it was found that its prediction coverage was higher than that pearson's correlation coefficient as well as vector similarity.

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A Study on the Maximizing Coverage for Recommender System

  • Lee, Hee-Choon;Lee, Seok-Jun;Park, Ji-Won;Kim, Chul-Seoung
    • 한국데이터정보과학회:학술대회논문집
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    • 2006.11a
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    • pp.119-128
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    • 2006
  • The similarity weight, the pearson's correlation coefficient, which is used in the recommender system has a weak point that it cannot predict all of the prediction value. The similarity weight, the vector similarity, has a weak point of the high MAE although the prediction coverage using the vector similarity is higher than that using the pearson's correlation coefficient. The purpose of this study is to suggest how to raise the prediction coverage. Also, the MAE using the suggested method in this study was compared both with the MAE using the pearson's correlation coefficient and with the MAE using the vector similarity, so was the prediction coverage. As a result, it was found that the low of the MAE in the case of using the suggested method was higher than that using the pearson's correlation coefficient. However, it was also shown that it was lower than that using the vector similarity In terms of the prediction coverage, when the suggested method was compared with two similarity weights as I mentioned above, it was found that its prediction coverage was higher than that pearson's correlation coefficient as well as vector similarity.

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On the Effect of Significance of Correlation Coefficient for Recommender System

  • Lee, Hee-Choon
    • Journal of the Korean Data and Information Science Society
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    • v.17 no.4
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    • pp.1129-1139
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    • 2006
  • Pearson's correlation coefficient and vector similarity are generally applied to The users' similarity weight of user based recommender system. This study is needed to find that the correlation coefficient of similarity weight is effected by the number of pair response and significance probability. From the classified correlation coefficient by the significance probability test on the correlation coefficient and pair of response, the change of MAE is studied by comparing the predicted precision of the two. The results are experimentally related with the change of MAE from the significant correlation coefficient and the number of pair response.

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A weighted similarity coefficient method for manufacturing cell formation (제조셀 형성을 위한 가중치 유사성계수 방법)

  • Oh, Soo-Cheol;Cho, Kyu-Kab
    • Journal of Korean Institute of Industrial Engineers
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    • v.22 no.1
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    • pp.141-154
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    • 1996
  • This paper presents a similarity coefficient based approach to the problem of machine-part grouping for cellular manufacturing. The method uses relevant production data such as part type, production volume, routing sequence to make machine cells and part families for cell formation. A new similarity coefficient using weighted factors is introduced and an algorithm for formation of machine cells and part families is developed. A comparative study of two similarity coefficient methods, Gupta and Seifoddini's method and the proposed method, is conducted.

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Improving Performance of Jaccard Coefficient for Collaborative Filtering

  • Lee, Soojung
    • Journal of the Korea Society of Computer and Information
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    • v.21 no.11
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    • pp.121-126
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    • 2016
  • In recommender systems based on collaborative filtering, measuring similarity is very critical for determining the range of recommenders. Data sparsity problem is fundamental in collaborative filtering systems, which is partly solved by Jaccard coefficient combined with traditional similarity measures. This study proposes a new coefficient for improving performance of Jaccard coefficient by compensating for its drawbacks. We conducted experiments using datasets of various characteristics for performance analysis. As a result of comparison between the proposed and the similarity metric of Pearson correlation widely used up to date, it is found that the two metrics yielded competitive performance on a dense dataset while the proposed showed much better performance on a sparser dataset. Also, the result of comparing the proposed with Jaccard coefficient showed that the proposed yielded far better performance as the dataset is denser. Overall, the proposed coefficient demonstrated the best prediction and recommendation performance among the experimented metrics.

A weighted similarity coefficient method for manufacturing cell formation (제조셀 형성을 위한 가중치 유사성계수 방법)

  • 오수철;조규갑
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 1995.04a
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    • pp.122-129
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    • 1995
  • This paper presents a similarity coefficient based approach to the problem of machine-part grouping for cellular manufacturing. The method uses relevant production data such as part type, production volume, routing sequence to make machine cells and part families for cell formation. A new similarity coefficient using weighted factors is introduced and an algorithm for formation of machine cells and part families is developed. A comparative study of two similarity coefficients - Gupta and seifoddini's method and proposed method - is conducted. A software program using TURBO C has been developed to verify the implementation.

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Comparative Study on the Measures of Similarity for the Location Template Matching(LTM) Method (Location Template Matching(LTM) 방법에 사용되는 유사성 척도들의 비교 연구)

  • Shin, Kihong
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.4
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    • pp.310-316
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    • 2014
  • The location template matching(LTM) method is a technique of identifying an impact location on a structure, and requires a certain measure of similarity between two time signals. In general, the correlation coefficient is widely used as the measure of similarity, while the group delay based method is recently proposed to improve the accuracy of the impact localization. Another possible measure is the frequency response assurance criterion(FRAC), though this has not been applied yet. In this paper, these three different measures of similarity are examined comparatively by using experimental data in order to understand the properties of these measures of similarity. The comparative study shows that the correlation coefficient and the FRAC give almost the same information while the group delay based method gives the shape oriented information that is best suitable for the location template matching method.

Comparative Study on the Measures of Similarity for the Location Template Matching (LTM) Method (Location Template Matching(LTM) 방법에 사용되는 유사성 척도들의 비교 연구)

  • Shin, Kihong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.04a
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    • pp.506-511
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    • 2014
  • The location template matching (LTM) method is a technique of identifying an impact location on a structure, and requires a certain measure of similarity between two time signals. In general, the correlation coefficient is widely used as the measure of similarity, while the group delay based method is recently proposed to improve the accuracy of the impact localization. Another possible measure is the frequency response assurance criterion (FRAC), though this has not been applied yet. In this paper, these three different measures of similarity are examined comparatively by using experimental data in order to understand the properties of these measures of similarity. The comparative study shows that the correlation coefficient and the FRAC give almost the same information while the group delay based method gives the shape oriented information that is best suitable for the location template matching method.

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A Study on the Effect of Co-Ratings and Correlation Coefficient for Recommender System

  • Lee, Hee-Choon;Lee, Seok-Jun;Park, Ji-Won;Kim, Chul-Seung
    • 한국데이터정보과학회:학술대회논문집
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    • 2006.11a
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    • pp.59-69
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    • 2006
  • Pearson's correlation coefficient and Vector similarity are generally applied to The users' similarity weight of user based recommender system. This study is needed to find that the correlation coefficient of similarity weight is effected by the number of pair response and significance probability. From the classified correlation coefficient by the significance probability test on the correlation coefficient and pair of response, the change of MAE is studied by comparing the predicted precision of the two. The results are experimentally related with the change of MAE from the significant correlation coefficient and the number of pair response.

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Image Recognition by Using Hybrid Coefficient Measure of Correlation and Distance (상관계수과 거리계수의 조합형 척도를 이용한 영상인식)

  • Hong, Seong-Jun;Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.3
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    • pp.343-347
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    • 2010
  • This paper presents an efficient image recognition method using the hybrid coefficient measure of correlation and distance. The correlation coefficient is applied to measure the statistical similarity by using Pearson coefficient, and distance coefficient is also applied to measure the spacial similarity by using city-block. The total similarity among images is calculated by extending the similarity between the feature vectors, then the feature vectors can be extracted by PCA and ICA, respectively. The proposed method has been applied to the problem for recognizing the 960(30 persons * 4 expressions * 2 lights * 4 poses) facial images of 40*50 pixels. The experimental results show that the proposed method of ICA has a superior recognition performances than the method using PCA, and is affected less by the environmental influences so as lighting.