• Title/Summary/Keyword: Bayes decision

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Corresponding between Error Probabilities and Bayesian Wrong Decision Lasses in Flexible Two-stage Plans

  • Ko, Seoung-gon
    • Journal of the Korean Statistical Society
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    • v.29 no.4
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    • pp.435-441
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    • 2000
  • Ko(1998, 1999) proposed certain flexible two-stage plans that could be served as one-step interim analysis in on-going clinical trials. The proposed Plans are optimal simultaneously in both a Bayes and a Neyman-Pearson sense. The Neyman-Pearson interpretation is that average expected sample size is being minimized, subject just to the two overall error rates $\alpha$ and $\beta$, respectively of first and second kind. The Bayes interpretation is that Bayes risk, involving both sampling cost and wrong decision losses, is being minimized. An example of this correspondence are given by using a binomial setting.

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Machine Learning Based Keyphrase Extraction: Comparing Decision Trees, Naïve Bayes, and Artificial Neural Networks

  • Sarkar, Kamal;Nasipuri, Mita;Ghose, Suranjan
    • Journal of Information Processing Systems
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    • v.8 no.4
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    • pp.693-712
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    • 2012
  • The paper presents three machine learning based keyphrase extraction methods that respectively use Decision Trees, Na$\ddot{i}$ve Bayes, and Artificial Neural Networks for keyphrase extraction. We consider keyphrases as being phrases that consist of one or more words and as representing the important concepts in a text document. The three machine learning based keyphrase extraction methods that we use for experimentation have been compared with a publicly available keyphrase extraction system called KEA. The experimental results show that the Neural Network based keyphrase extraction method outperforms two other keyphrase extraction methods that use the Decision Tree and Na$\ddot{i}$ve Bayes. The results also show that the Neural Network based method performs better than KEA.

Moving Object Tracking in Active Camera Environment Based on Bayes Decision Theory (Bayes 결정이론에 기반을 둔 능동카메라 환경에서의 이동 물체의 검출 및 추적)

  • 배수현;강문기
    • Journal of Broadcast Engineering
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    • v.4 no.1
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    • pp.22-31
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    • 1999
  • Moving object tracking improves the efficiency and qualification for observation system, broadcasting system, video conference, etc. This paper propcses an improved Bayes decision method for detecting and tracking moving objects in active camera environment. The Bayes decision based tracking approach finds the region of moving objects by analyzing the image sequences statistically. The propcsed algorithm regenerates the probability density function to accord with moving objects and background for active camera. Experimental results show that the algorithm is accurate. reliable and noise resistant. The result is compared with those of the conventional methods.

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Effect of Nonnormality on Bayes Decision Function for Testing Normal Mean

  • Bansal, Ashok K.
    • Journal of the Korean Statistical Society
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    • v.8 no.1
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    • pp.15-21
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    • 1979
  • A zone of sensitivity is developed to investigate the effect of nonnormality on the Bayes decision function for testing mean of a normal population when either parent or prior belongs to Edgeworthian family of moderately nonnormal probability density functions.

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Breast Cancer Diagnosis using Naive Bayes Analysis Techniques (Naive Bayes 분석기법을 이용한 유방암 진단)

  • Park, Na-Young;Kim, Jang-Il;Jung, Yong-Gyu
    • Journal of Service Research and Studies
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    • v.3 no.1
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    • pp.87-93
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    • 2013
  • Breast cancer is known as a disease that occurs in a lot of developed countries. However, in recent years, the incidence of Korea's modern woman is increased steadily. As well known, breast cancer usually occurs in women over 50. In the case of Korea, however, the incidence of 40s with young women is increased steadily than the West. Therefore, it is a very urgent task to build a manual to the accurate diagnosis of breast cancer in adult women in Korea. In this paper, we show how using data mining techniques to predict breast cancer. Data mining refers to the process of finding regular patterns or relationships among variables within the database. To this, sophisticated analysis using the model, you will find useful information that is easily revealed. In this paper, through experiments Deicion Tree Naive Bayes analysis techniques were compared using analysis techniques to diagnose breast cancer. Two algorithms was analyzed by applying C4.5 algorithm. Deicison Tree classification accuracy was fairly good. Naive Bayes classification method showed better accuracy compared to the Decision Tree method.

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Multimedia Watermark Detection Algorithm Based on Bayes Decision Theory (Bayes 판단 이론 기반 멀티미디어 워터마크 검출 알고리즘)

  • 권성근;이석환;김병주;권기구;하인성;권기룡;이건일
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.7A
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    • pp.695-704
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    • 2002
  • Watermark detection plays a crucial role in multimedia copyright protection and has traditionally been tackled using correlation-based algorithms. However, correlation-based detection is not actually the best choice, as it does not utilize the distributional characteristics of the image being marked. Accordingly, an efficient watermark detection scheme for DWT coefficients is proposed as optimal for non-additive schemes. Based on the statistical decision theory, the proposed method is derived according to Bayes decision theory, the Neyman-Pearson criterion, and the distribution of the DWT coefficients, thereby minimizing the missed detection probability subject to a given false alarm probability. The proposed method was tested in the context of robustness, and the results confirmed the superiority of the proposed technique over conventional correlation-based detection method.

Empirical Bayes Pproblems with Dependent and Nonidentical Components

  • Inha Jung;Jee-Chang Hong;Kang Sup Lee
    • Communications for Statistical Applications and Methods
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    • v.2 no.1
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    • pp.145-154
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    • 1995
  • Empirical Bayes approach is applied to estimation of the binomial parameter when there is a cost for observations. Both the sample size and the decision rule for estimating the parameter are determined stochastically by the data, making the result more useful in applications. Our empirical Bayes problems with non-iid components are compared to the usual empirical Bayes problems with iid components. The asymptotic optimal procedure with a computer simulation is given.

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Comparative Study of Machine learning Techniques for Spammer Detection in Social Bookmarking Systems (소셜 복마킹 시스템의 스패머 탐지를 위한 기계학습 기술의 성능 비교)

  • Kim, Chan-Ju;Hwang, Kyu-Baek
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.5
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    • pp.345-349
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    • 2009
  • Social bookmarking systems are a typical web 2.0 service based on folksonomy, providing the platform for storing and sharing bookmarking information. Spammers in social bookmarking systems denote the users who abuse the system for their own interests in an improper way. They can make the entire resources in social bookmarking systems useless by posting lots of wrong information. Hence, it is important to detect spammers as early as possible and protect social bookmarking systems from their attack. In this paper, we applied a diverse set of machine learning approaches, i.e., decision tables, decision trees (ID3), $na{\ddot{i}}ve$ Bayes classifiers, TAN (tree-augment $na{\ddot{i}}ve$ Bayes) classifiers, and artificial neural networks to this task. In our experiments, $na{\ddot{i}}ve$ Bayes classifiers performed significantly better than other methods with respect to the AUC (area under the ROC curve) score as veil as the model building time. Plausible explanations for this result are as follows. First, $na{\ddot{i}}ve$> Bayes classifiers art known to usually perform better than decision trees in terms of the AUC score. Second, the spammer detection problem in our experiments is likely to be linearly separable.

Classification Accuracy Improvement for Decision Tree (의사결정트리의 분류 정확도 향상)

  • Rezene, Mehari Marta;Park, Sanghyun
    • Proceedings of the Korea Information Processing Society Conference
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    • 2017.04a
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    • pp.787-790
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    • 2017
  • Data quality is the main issue in the classification problems; generally, the presence of noisy instances in the training dataset will not lead to robust classification performance. Such instances may cause the generated decision tree to suffer from over-fitting and its accuracy may decrease. Decision trees are useful, efficient, and commonly used for solving various real world classification problems in data mining. In this paper, we introduce a preprocessing technique to improve the classification accuracy rates of the C4.5 decision tree algorithm. In the proposed preprocessing method, we applied the naive Bayes classifier to remove the noisy instances from the training dataset. We applied our proposed method to a real e-commerce sales dataset to test the performance of the proposed algorithm against the existing C4.5 decision tree classifier. As the experimental results, the proposed method improved the classification accuracy by 8.5% and 14.32% using training dataset and 10-fold crossvalidation, respectively.

Empirical Bayes Problem With Random Sample Size Components

  • Jung, Inha
    • Journal of the Korean Statistical Society
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    • v.20 no.1
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    • pp.67-76
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    • 1991
  • The empirical Bayes version involves ″independent″ repetitions(a sequence) of the component decision problem. With the varying sample size possible, these are not identical components. However, we impose the usual assumption that the parameters sequence $\theta$=($\theta$$_1$, $\theta$$_2$, …) consists of independent G-distributed parameters where G is unknown. We assume that G $\in$ g, a known family of distributions. The sample size $N_i$ and the decisin rule $d_i$ for component i of the sequence are determined in an evolutionary way. The sample size $N_1$ and the decision rule $d_1$$\in$ $D_{N1}$ used in the first component are fixed and chosen in advance. The sample size $N_2$and the decision rule $d_2$ are functions of *see full text($\underline{X}^1$equation omitted), the observations in the first component. In general, $N_i$ is an integer-valued function of *see full text(equation omitted) and, given $N_i$, $d_i$ is a $D_{Ni}$/-valued function of *see full text(equation omitted). The action chosen in the i-th component is *(equation omitted) which hides the display of dependence on *(equation omitted). We construct an empirical Bayes decision rule for estimating normal mean and show that it is asymptotically optimal.

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