• Title/Summary/Keyword: Bayes theory

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Highly Reliable Watermark Detection Algorithm using Statistical Decision Method in Wavelet Domain (웨이블릿 영역에서 통계적 판정법을 이용한 고신뢰 워터마크 검출 알고리즘)

  • 권성근;김병주;이석환;권기구;김영춘;권기룡;이건일
    • Journal of Korea Multimedia Society
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    • v.6 no.1
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    • pp.67-77
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    • 2003
  • Watermark detection has a crucial role in copyright protection and authentication for multimedia Because be the correlation -based algorithm which has widely been used in the watermark detection doesn't utilize the distributional characteristics of cover image to be marked, its performance is not optimum. So a new detection algorithm is proposed which is optimum for multiplicative watermark embedding. By relying on statistical decision method, the proposed method is derived according to the Bayes decision theory. Neyman Pearson criterion, and distribution of wavelet coefficients, thus Permitting to minimize the missed detection probability subject to a given false detection probability The superiority of the proposed method has been tested from a robustness perspective. The results confirm the superiority of the proposed technique over classical correlation -based method.

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A Study on the Processing Method of Reliability Database using 2-Bayes Theory (2-Bayes 이론을 이용한 데이터 처리방법에 관한 연구)

  • Lee, M.S.;Rhie, K.W.;Kim, T.H.;Yoon, I.K.;Oh, Y.D.;Seo, D.H.
    • Journal of the Korean Society of Safety
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    • v.24 no.6
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    • pp.144-149
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    • 2009
  • The safety assessment for facility industry is now being periodically performed in Korea. For the purpose of scientific safety management, QRA(Quantitative Risk Assessment) is also being performed, and reliability data of the facilities is essential to perform the assessment. The necessary reliability data for QRA have been generally announced the values in other process industries, which results in the drop of risk reliability. The most appropriate method is to perform a direct reliability analysis towards the facilities undergoing safety assessment. In this study, the distinction between homogeneous sample estimation and multi-sample estimation of reliability data clarify using 2-Bayes theory.

Bayesian Model Selection in Analysis of Reciprocals

  • Kang, Sang-Gil;Kim, Dal-Ho
    • 한국데이터정보과학회:학술대회논문집
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    • 2005.10a
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    • pp.85-93
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    • 2005
  • Tweedie (1957a) proposed a method for the analysis of residuals from an inverse Gaussian population paralleling the analysis of variance in normal theory. He called it the analysis of reciprocals. In this paper, we propose a Bayesian model selection procedure based on the fractional Bayes factor for the analysis of reciprocals. Using the proposed model procedures, we compare with the classical tests.

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Bayesian Model Selection in Analysis of Reciprocals

  • Kang, Sang-Gil;Kim, Dal-Ho;Cha, Young-Joon
    • Journal of the Korean Data and Information Science Society
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    • v.16 no.4
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    • pp.1167-1176
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    • 2005
  • Tweedie (1957a) proposed a method for the analysis of residuals from an inverse Gaussian population paralleling the analysis of variance in normal theory. He called it the analysis of reciprocals. In this paper, we propose a Bayesian model selection procedure based on the fractional Bayes factor for the analysis of reciprocals. Using the proposed model selection procedures, we compare with the classical tests.

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Multimedia Watermark Detection Algorithm Based on Bayes Decision Theorys

  • Kwon, Seong-Geun;Lee, Suk-Hwan;Kwon, Kee-Koo;Kwon, Ki-Ryong;Lee, Kuhn-Il
    • Proceedings of the IEEK Conference
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    • 2002.07b
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    • pp.1272-1275
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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.

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Empirical Bayes Posterior Odds Ratio for Heteroscedastic Classification

  • Kim, Hea-Jung
    • Journal of the Korean Statistical Society
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    • v.16 no.2
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    • pp.92-101
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    • 1987
  • Our interest is to access in some way teh relative odds or probability that a multivariate observation Z belongs to one of k multivariate normal populations with unequal covariance matrices. We derived the empirical Bayes posterior odds ratio for the classification rule when population parameters are unknown. It is a generalization of the posterior odds ratio suggested by Gelsser (1964). The classification rule does not have complicated distribution theory which a large variety of techniques from the sampling viewpoint have. The proposed posterior odds ratio is compared to the Gelsser's posterior odds ratio through a Monte Carlo study. The results show that the empiricla Bayes posterior odds ratio, in general, performs better than the Gelsser's. Especially, for large dimension of Z and small training sample, the performance is prominent.

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Maximum penalized likelihood estimation for a stress-strength reliability model using complete and incomplete data

  • Hassan, Marwa Khalil
    • Communications for Statistical Applications and Methods
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    • v.25 no.4
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    • pp.355-371
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    • 2018
  • The two parameter negative exponential distribution has many practical applications in queuing theory such as the service times of agents in system, the time it takes before your next telephone call, the time until a radioactive practical decays, the distance between mutations on a DNA strand, and the extreme values of annual snowfall or rainfall; consequently, has many applications in reliability systems. This paper considers an estimation problem of stress-strength model with two parameter negative parameter exponential distribution. We introduce a maximum penalized likelihood method, Bayes estimator using Lindley approximation to estimate stress-strength model and compare the proposed estimators with regular maximum likelihood estimator for complete data. We also introduce a maximum penalized likelihood method, Bayes estimator using a Markov chain Mote Carlo technique for incomplete data. A Monte Carlo simulation study is performed to compare stress-strength model estimates. Real data is used as a practical application of the proposed model.

An Improved Homonym Disambiguation Model based on Bayes Theory (Bayes 정리에 기반한 개선된 동형이의어 분별 모텔)

  • 김창환;이왕우
    • Journal of the Korea Computer Industry Society
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    • v.2 no.12
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    • pp.1581-1590
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    • 2001
  • This paper asserted more developmental model of WSD(word sense disambiguation) than J. Hur(2000)'s WSD model. This model suggested an improved statistical homonym disambiguation Model based on Bayes Theory. This paper using semantic information(co-occurrence data) obtained from definitions of part of speech(POS) tagged UMRD-S(Ulsan university Machine Readable Dictionary(Semantic Tagged)). we extracted semantic features in the context as nouns, predicates and adverbs from the definitions in the korean dictionary. In this research, we make an experiment with the accuracy of WSD system about major nine homonym nouns and new seven homonym predicates supplementary. The inner experimental result showed average accuracy of 98.32% with regard to the most Nine homonym nouns and 99.53% for the Seven homonym predicates. An Addition, we save test on Korean Information Base and ETRI's POS tagged corpus. This external experimental result showed average accuracy of 84.42% with regard to the most Nine nouns over unsupervised learning sentences from Korean Information Base and ETRI Corpus, 70.81 % accuracy rate for the Seven predicates from Sejong Project phrase part tagging corpus (3.5 million phrases) too.

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ON CONSISTENCY OF SOME NONPARAMETRIC BAYES ESTIMATORS WITH RESPECT TO A BETA PROCESS BASED ON INCOMPLETE DATA

  • Hong, Jee-Chang;Jung, In-Ha
    • The Pure and Applied Mathematics
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    • v.5 no.2
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    • pp.123-132
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    • 1998
  • Let F and G denote the distribution functions of the failure times and the censoring variables in a random censorship model. Susarla and Van Ryzin(1978) verified consistency of $F_{\alpha}$, he NPBE of F with respect to the Dirichlet process prior D($\alpha$), in which they assumed F and G are continuous. Assuming that A, the cumulative hazard function, is distributed according to a beta process with parameters c, $\alpha$, Hjort(1990) obtained the Bayes estimator $A_{c,\alpha}$ of A under a squared error loss function. By the theory of product-integral developed by Gill and Johansen(1990), the Bayes estimator $F_{c,\alpha}$ is recovered from $A_{c,\alpha}$. Continuity assumption on F and G is removed in our proof of the consistency of $A_{c,\alpha}$ and $F_{c,\alpha}$. Our result extends Susarla and Van Ryzin(1978) since a particular transform of a beta process is a Dirichlet process and the class of beta processes forms a much larger class than the class of Dirichlet processes.

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A Study on the Quantitative Determination of Failure Effect Probability for Criticality Analysis on System (시스템의 치명도 분석을 위한 고장영향확률 정량화 방안 연구)

  • Lee, Myeong-seok;Choi, Seong-Dae;Hur, Jang-wook
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.18 no.8
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    • pp.31-37
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    • 2019
  • The inter-development of FMECA is very important to assess the effect of potential failures during system operation on mission, safety and performance. Among these, criticality analysis is a core task that identifies items with high risk and selects the analyzed objects as the key management targets and reflects their effects to the design optimization. In this paper, we analyze the theory related to criticality analysis following US military standard, and propose a method to quantify the failure effect probability for objective criticality analysis. The criticality analysis according to the US military standard depends on the subjective judgment of the failure probability. The methodology for quantifying the failure effect probability is presented by using the reliability theory and the Bayes theorem. The failure rate is calculated by applying the method to quantify failure effect probability.