[1]QIAN Dong,WANG Bei,ZHANG Tao,et al.Classification algorithm based on Copula theory and Bayesian decision theory[J].CAAI Transactions on Intelligent Systems,2016,11(1):78-83.[doi:10.11992/tis.201509011]
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CAAI Transactions on Intelligent Systems[ISSN 1673-4785/CN 23-1538/TP] Volume:
11
Number of periods:
2016 1
Page number:
78-83
Column:
学术论文—机器学习
Public date:
2016-02-25
- Title:
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Classification algorithm based on Copula theory and Bayesian decision theory
- Author(s):
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QIAN Dong1; WANG Bei1; ZHANG Tao2; WANG Xingyu1
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1. School of Information Science and Engineering, East China University of Science and Technology, Shanghai 200237, China;
2. Department of Automation, Tsinghua University, Beijing 100086, China
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- Keywords:
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machine learning; Bayesian decision theory; Copula theory; kernel density estimation; physiological signals
- CLC:
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TP391.4
- DOI:
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10.11992/tis.201509011
- Abstract:
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Traditional Bayesian decision classification algorithm is easily affected by the estimation of class-conditional probability densities, a fact that may result in incorrect classification results. Therefore, this paper proposes an improved classification algorithm based on Bayesian decision, i.e., Bayesian-Copula Discriminant Classifier (BCDC). This method constructs class-conditional probability densities by combining Copula theory and kernel density estimation instead of making assumptions on the form of class-conditional probability densities. Kernel density estimation is used to smooth the probability distribution of each feature. By performing probability integral transform, continuous distribution is converted to random variables having a uniform distribution. Then, Copula functions are used to construct the dependency structure between these probability distributions for two categories. Moreover, the maximum likelihood estimation is applied to determine the parameters of Copula functions, and two well-fitted Copula functions for two categories are selected based on Bayesian information criterion. The BCDC method was validated with experimental datasets of physiological signals. The obtained results showed that the proposed method outperforms other traditional methods in terms of classification accuracy and AUC as well as robustness. Moreover, it takes full advantage of Copula theory and kernel density estimation and improves the accuracy and flexibility of the estimation.