• Title/Summary/Keyword: bayesian classifier

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Emotion Classification Using EEG Spectrum Analysis and Bayesian Approach (뇌파 스펙트럼 분석과 베이지안 접근법을 이용한 정서 분류)

  • Chung, Seong Youb;Yoon, Hyun Joong
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.37 no.1
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    • pp.1-8
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    • 2014
  • This paper proposes an emotion classifier from EEG signals based on Bayes' theorem and a machine learning using a perceptron convergence algorithm. The emotions are represented on the valence and arousal dimensions. The fast Fourier transform spectrum analysis is used to extract features from the EEG signals. To verify the proposed method, we use an open database for emotion analysis using physiological signal (DEAP) and compare it with C-SVC which is one of the support vector machines. An emotion is defined as two-level class and three-level class in both valence and arousal dimensions. For the two-level class case, the accuracy of the valence and arousal estimation is 67% and 66%, respectively. For the three-level class case, the accuracy is 53% and 51%, respectively. Compared with the best case of the C-SVC, the proposed classifier gave 4% and 8% more accurate estimations of valence and arousal for the two-level class. In estimation of three-level class, the proposed method showed a similar performance to the best case of the C-SVC.

Accelerating the EM Algorithm through Selective Sampling for Naive Bayes Text Classifier (나이브베이즈 문서분류시스템을 위한 선택적샘플링 기반 EM 가속 알고리즘)

  • Chang Jae-Young;Kim Han-Joon
    • The KIPS Transactions:PartD
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    • v.13D no.3 s.106
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    • pp.369-376
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    • 2006
  • This paper presents a new method of significantly improving conventional Bayesian statistical text classifier by incorporating accelerated EM(Expectation Maximization) algorithm. EM algorithm experiences a slow convergence and performance degrade in its iterative process, especially when real online-textual documents do not follow EM's assumptions. In this study, we propose a new accelerated EM algorithm with uncertainty-based selective sampling, which is simple yet has a fast convergence speed and allow to estimate a more accurate classification model on Naive Bayesian text classifier. Experiments using the popular Reuters-21578 document collection showed that the proposed algorithm effectively improves classification accuracy.

Band Selection Using Forward Feature Selection Algorithm for Citrus Huanglongbing Disease Detection

  • Katti, Anurag R.;Lee, W.S.;Ehsani, R.;Yang, C.
    • Journal of Biosystems Engineering
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    • v.40 no.4
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    • pp.417-427
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    • 2015
  • Purpose: This study investigated different band selection methods to classify spectrally similar data - obtained from aerial images of healthy citrus canopies and citrus greening disease (Huanglongbing or HLB) infected canopies - using small differences without unmixing endmember components and therefore without the need for an endmember library. However, large number of hyperspectral bands has high redundancy which had to be reduced through band selection. The objective, therefore, was to first select the best set of bands and then detect citrus Huanglongbing infected canopies using these bands in aerial hyperspectral images. Methods: The forward feature selection algorithm (FFSA) was chosen for band selection. The selected bands were used for identifying HLB infected pixels using various classifiers such as K nearest neighbor (KNN), support vector machine (SVM), naïve Bayesian classifier (NBC), and generalized local discriminant bases (LDB). All bands were also utilized to compare results. Results: It was determined that a few well-chosen bands yielded much better results than when all bands were chosen, and brought the classification results on par with standard hyperspectral classification techniques such as spectral angle mapper (SAM) and mixture tuned matched filtering (MTMF). Median detection accuracies ranged from 66-80%, which showed great potential toward rapid detection of the disease. Conclusions: Among the methods investigated, a support vector machine classifier combined with the forward feature selection algorithm yielded the best results.

A Study on the Classification for Satellite Images using Hybrid Method (하이브리드 분류기법을 이용한 위성영상의 분류에 관한 연구)

  • Jeon, Young-Joon;Kim, Jin-Il
    • The KIPS Transactions:PartB
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    • v.11B no.2
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    • pp.159-168
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    • 2004
  • This paper presents hybrid classification method to improve the performance of satellite images classification by combining Bayesian maximum likelihood classifier, ISODATA clustering and fuzzy C-Means algorithm. In this paper, the training data of each class were generated by separating the spectral signature using ISODATA clustering. We can classify according to pixel's membership grade followed by cluster center of fuzzy C-Means algorithm as the mean value of training data for each class. Bayesian maximum likelihood classifier is performed with prior probability by result of fuzzy C-Means classification. The results shows that proposed method could improve performance of classification method and also perform classification with no concern about spectral signature of the training data. The proposed method Is applied to a Landsat TM satellite image for the verifying test.

Classification of Welding Defects in Austenitic Stainless Steel by Neural Pattern Recognition of Ultrasonic Signal (초음파신호의 신경망 형상인식법을 이용한 오스테나이트 스테인레스강의 용접부결함 분류에 관한 연구)

  • Lee, Gang-Yong;Kim, Jun-Seop
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.4
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    • pp.1309-1319
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    • 1996
  • The research for the classification of the natural defects in welding zone is performd using the neuro-pattern recognition technology. The signal pattern recognition package including the user's defined function is developed to perform the digital signal processing, feature extraction, feature selection and classifier selection, The neural network classifier and the statistical classifiers such as the linear discriminant function classifier and the empirical Bayesian calssifier are compared and discussed. The neuro-pattern recognition technique is applied to the classificaiton of such natural defects as root crack, incomplete penetration, lack of fusion, slag inclusion, porosity, etc. If appropriately learned, the neural network classifier is concluded to be better than the statistical classifiers in the classification of the natural welding defects.

Pattern Classification Methods for Keystroke Identification (키스트로크 인식을 위한 패턴분류 방법)

  • Cho Tai-Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.5
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    • pp.956-961
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    • 2006
  • Keystroke time intervals can be a discriminating feature in the verification and identification of computer users. This paper presents a comparison result obtained using several classification methods including k-NN (k-Nearest Neighbor), back-propagation neural networks, and Bayesian classification for keystroke identification. Performance of k-NN classification was best with small data samples available per user, while Bayesian classification was the most superior to others with large data samples per user. Thus, for web-based on-line identification of users, it seems to be appropriate to selectively use either k-NN or Bayesian method according to the number of keystroke samples accumulated by each user.

Evaluation of Bayesian Model Averaging (BMA) of Bayesian Network Classifiers (BNCs) on Small Datasets (작은 데이터에 대한 베이지안망 분류기(BNC)의 베이지안 모델 평균화(BMA) 성능 평가)

  • 황규백;장병탁
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.10a
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    • pp.22-24
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    • 2003
  • 작은 데이터에서 베이지안망 분류기(Bayesian network classifier, BNC)를 학습할 때, 과대적합(overfitting)으로 인한 일반화 성능의 저하가 초래된다 이런 경우, 베이지안 모델 평균화(Bayesian model averaging, BMA)는 모델 자체에 대한 불확실성을 분석 과정에서 고려함으로써, 성능 저하를 피할 수 있는 수단을 제공한다. 본 논문에서는 BNC의 BMA의 작은 데이터에 대한 성능을 평가 및 분석한다. 특히, 노드의 순서에 대한 평균화의 효과가 연구된다. 인공데이터에 대한 실험 결과, 노드의 순서가 BNC의 BMA의 분류 성능에 미치는 영향은 지대하며, 이는 데이터의 크기가 극히 작은 경우의 성능 저하에 직접적인 원인이 된다.

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Simple Bayesian Model for Improvement of Collaborative Filtering (협업 필터링 개선을 위한 베이지안 모형 개발)

  • Lee, Young-Chan
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2005.05a
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    • pp.232-239
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    • 2005
  • Collaborative-filtering-enabled Web sites that recommend books, CDs, movies, and so on, have become very popular on the Internet. Such sites recommend items to a user on the basis of the opinions of other users with similar tastes. This paper discuss an approach to collaborative filtering based on the Simple Bayesian and apply this model to two variants of the collaborative filtering. One is user-based collaborative filtering, which makes predictions based on the users' similarities. The other is item-based collaborative filtering which makes predictions based on the items' similarities. To evaluate the proposed algorithms, this paper used a database of movie recommendations. Empirical results show that the proposed Bayesian approaches outperform typical correlation-based collaborative filtering algorithms.

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Recognition of Korean Vowels using Bayesian Classification with Mouth Shape (베이지안 분류 기반의 입 모양을 이용한 한글 모음 인식 시스템)

  • Kim, Seong-Woo;Cha, Kyung-Ae;Park, Se-Hyun
    • Journal of Korea Multimedia Society
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    • v.22 no.8
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    • pp.852-859
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    • 2019
  • With the development of IT technology and smart devices, various applications utilizing image information are being developed. In order to provide an intuitive interface for pronunciation recognition, there is a growing need for research on pronunciation recognition using mouth feature values. In this paper, we propose a system to distinguish Korean vowel pronunciations by detecting feature points of lips region in images and applying Bayesian based learning model. The proposed system implements the recognition system based on Bayes' theorem, so that it is possible to improve the accuracy of speech recognition by accumulating input data regardless of whether it is speaker independent or dependent on small amount of learning data. Experimental results show that it is possible to effectively distinguish Korean vowels as a result of applying probability based Bayesian classification using only visual information such as mouth shape features.

Bayesian Network-based Data Analysis for Diagnosing Retinal Disease (망막 질환 진단을 위한 베이지안 네트워크에 기초한 데이터 분석)

  • Kim, Hyun-Mi;Jung, Sung-Hwan
    • Journal of Korea Multimedia Society
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    • v.16 no.3
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    • pp.269-280
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    • 2013
  • In this paper, we suggested the possibility of using an efficient classifier for the dependency analysis of retinal disease. First, we analyzed the classification performance and the prediction accuracy of GBN (General Bayesian Network), GBN with reduced features by Markov Blanket and TAN (Tree-Augmented Naive Bayesian Network) among the various bayesian networks. And then, for the first time, we applied TAN showing high performance to the dependency analysis of the clinical data of retinal disease. As a result of this analysis, it showed applicability in the diagnosis and the prediction of prognosis of retinal disease.