• Title/Summary/Keyword: Gibbs Sampling method

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Multiple Comparisons for a Bivariate Exponential Populations Based On Dirichlet Process Priors

  • Cho, Jang-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.18 no.2
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    • pp.553-560
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    • 2007
  • In this paper, we consider two components system which lifetimes have Freund's bivariate exponential model with equal failure rates. We propose Bayesian multiple comparisons procedure for the failure rates of I Freund's bivariate exponential populations based on Dirichlet process priors(DPP). The family of DPP is applied in the form of baseline prior and likelihood combination to provide the comparisons. Computation of the posterior probabilities of all possible hypotheses are carried out through Markov Chain Monte Carlo(MCMC) method, namely, Gibbs sampling, due to the intractability of analytic evaluation. The whole process of multiple comparisons problem for the failure rates of bivariate exponential populations is illustrated through a numerical example.

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Bayesian Hierarchical Mixed Effects Analysis of Time Non-Homogeneous Markov Chains (계층적 베이지안 혼합 효과 모델을 사용한 비동차 마코프 체인의 분석)

  • Sung, Minje
    • The Korean Journal of Applied Statistics
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    • v.27 no.2
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    • pp.263-275
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    • 2014
  • The present study used a hierarchical Bayesian approach was used to develop a mixed effect model to describe the transitional behavior of subjects in time nonhomogeneous Markov chains. The posterior distributions of model parameters were not in analytically tractable forms; subsequently, a Gibbs sampling method was used to draw samples from full conditional posterior distributions. The proposed model was implemented with real data.

Method of Associative Group Using FP-Tree in Personalized Recommendation System (개인화 추천 시스템에서 FP-Tree를 이용한 연관 군집 방법)

  • Cho, Dong-Ju;Rim, Kee-Wook;Lee, Jung-Hyun;Chung, Kyung-Yong
    • The Journal of the Korea Contents Association
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    • v.7 no.10
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    • pp.19-26
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    • 2007
  • Since collaborative filtering has used the nearest-neighborhood method based on item preference it cannot only reflect exact contents but also has the problem of sparsity and scalability. The item-based collaborative filtering has been practically used improve these problems. However it still does not reflect attributes of the item. In this paper, we propose the method of associative group using the FP-Tree to solve the problem of existing recommendation system. The proposed makes frequent item and creates association rule by using FP-Tree without occurrence of candidate set. We made the efficient item group using $\alpha-cut$ according to the confidence of the association rule. To estimate the performance, the suggested method is compared with Gibbs Sampling, Expectation Maximization, and K-means in the MovieLens dataset.

Hierarchical Bayes Analysis of Longitudinal Poisson Count Data

  • Kim, Dal-Ho;Shin, Im-Hee;Choi, In-Sun
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.227-234
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    • 2002
  • In this paper, we consider hierarchical Bayes generalized linear models for the analysis of longitudinal count data. Specifically we introduce the hierarchical Bayes random effects models. We discuss implementation of the Bayes procedures via Markov chain Monte Carlo (MCMC) integration techniques. The hierarchical Baye method is illustrated with a real dataset and is compared with other statistical methods.

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Bayesian Estimation in Bioequivalence Study

  • Lee, Seung-Chun
    • The Korean Journal of Applied Statistics
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    • v.24 no.6
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    • pp.1095-1102
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    • 2011
  • The classical two-period, two-sequence crossover design is no longer sufficient to assess various demands in a bioequivalence study. For instance, to estimate the within-subject and between-subject variances of test and reference formulations separately, it is necessary to use a replicate design in which each subject receives at least the reference formulation in two periods. Several designs were studied to satisfy the demands. It is provided a unified Bayesian approach applicable to those study designs. The benefit of the method in the bioequivalence study is discussed.

Bayesian Analysis for Nonhomogeneous Poisson Process Software Reliability (비동질적 포아송과정을 사용한 소프트웨어 베이지안 신뢰성 분석에 관한 연구)

  • 김희철;이동철
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.22 no.49
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    • pp.23-31
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    • 1999
  • Bayesian approach using nonhomogeneous Poisson process is considered for modelling software reliability problem. The usefulness of the iterative sampling-based method increases greatly as the dimension of a problem increases. Maximum likelihood estimator and Gibbs estimator are derived. Model selection based on a predictive likelihood is studied. A numerical example is given.

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The Impact of Foreign Ownership on Capital Structure: Empirical Evidence from Listed Firms in Vietnam

  • NGUYEN, Van Diep;DUONG, Quynh Nga
    • The Journal of Asian Finance, Economics and Business
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    • v.9 no.2
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    • pp.363-370
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    • 2022
  • The study aims to probe the impact of foreign ownership on Vietnamese listed firms' capital structure. This study employs panel data of 288 non-financial firms listed on the Ho Chi Minh City stock exchange (HOSE) and Ha Noi stock exchange (HNX) in 2015-2019. In this research, we applied a Bayesian linear regression method to provide probabilistic explanations of the model uncertainty and effect of foreign ownership on the capital structure of non-financial listed enterprises in Vietnam. The findings of experimental analysis by Bayesian linear regression method through Markov chain Monte Carlo (MCMC) technique combined with Gibbs sampler suggest that foreign ownership has substantial adverse effects on the firms' capital structure. Our findings also indicate that a firm's size, age, and growth opportunities all have a strong positive and significant effect on its debt ratio. We found that the firms' profitability, tangible assets, and liquidity negatively and strongly affect firms' capital structure. Meanwhile, there is a low negative impact of dividends and inflation on the debt ratio. This research has ramifications for business managers since it improves a company's financial resources by developing a strong capital structure and considering foreign investment as a source of funding.

Korean Welfare Panel Data: A Computational Bayesian Method for Ordered Probit Random Effects Models

  • Lee, Hyejin;Kyung, Minjung
    • Communications for Statistical Applications and Methods
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    • v.21 no.1
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    • pp.45-60
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    • 2014
  • We introduce a MCMC sampling for a generalized linear normal random effects model with the ordered probit link function based on latent variables from suitable truncated normal distribution. Such models have proven useful in practice and we have observed numerically reasonable results in the estimation of fixed effects when the random effect term is provided. Applications that utilize Korean Welfare Panel Study data can be difficult to model; subsequently, we find that an ordered probit model with the random effects leads to an improved analyses with more accurate and precise inferences.

Geostatistics for Bayesian interpretation of geophysical data

  • Oh Seokhoon;Lee Duk Kee;Yang Junmo;Youn Yong-Hoon
    • 한국지구물리탐사학회:학술대회논문집
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    • 2003.11a
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    • pp.340-343
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    • 2003
  • This study presents a practical procedure for the Bayesian inversion of geophysical data by Markov chain Monte Carlo (MCMC) sampling and geostatistics. We have applied geostatistical techniques for the acquisition of prior model information, and then the MCMC method was adopted to infer the characteristics of the marginal distributions of model parameters. For the Bayesian inversion of dipole-dipole array resistivity data, we have used the indicator kriging and simulation techniques to generate cumulative density functions from Schlumberger array resistivity data and well logging data, and obtained prior information by cokriging and simulations from covariogram models. The indicator approach makes it possible to incorporate non-parametric information into the probabilistic density function. We have also adopted the MCMC approach, based on Gibbs sampling, to examine the characteristics of a posteriori probability density function and the marginal distribution of each parameter. This approach provides an effective way to treat Bayesian inversion of geophysical data and reduce the non-uniqueness by incorporating various prior information.

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The Bayesian Inference for Software Reliability Models Based on NHPP (NHPP에 기초한 소프트웨어 신뢰도 모형에 대한 베이지안 추론에 관한 연구)

  • Lee, Sang-Sik;Kim, Hui-Cheol;Song, Yeong-Jae
    • The KIPS Transactions:PartD
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    • v.9D no.3
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    • pp.389-398
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    • 2002
  • Software reliability growth models are used in testing stages of software development to model the error content and time intervals between software failures. This paper presents a stochastic model for the software failure phenomenon based on a nonhomogeneous Poisson process(NHPP) and performs Bayesian inference using prior information. The failure process is analyzed to develop a suitable mean value function for the NHPP ; expressions are given for several performance measure. Actual software failure data are compared with several model on the constant reflecting the quality of testing. The performance measures and parametric inferences of the suggested models using Rayleigh distribution and Laplace distribution are discussed. The results of the suggested models are applied to real software failure data and compared with Goel model. Tools of parameter point inference and 95% credible intereval was used method of Gibbs sampling. In this paper, model selection using the sum of the squared errors was employed. The numerical example by NTDS data was illustrated.