• Title/Summary/Keyword: Gibbs sampler

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A Bayesian uncertainty analysis for nonignorable nonresponse in two-way contingency table

  • Woo, Namkyo;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.6
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    • pp.1547-1555
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    • 2015
  • We study the problem of nonignorable nonresponse in a two-way contingency table and there may be one or two missing categories. We describe a nonignorable nonresponse model for the analysis of two-way categorical table. One approach to analyze these data is to construct several tables (one complete and the others incomplete). There are nonidentifiable parameters in incomplete tables. We describe a hierarchical Bayesian model to analyze two-way categorical data. We use a nonignorable nonresponse model with Bayesian uncertainty analysis by placing priors in nonidentifiable parameters instead of a sensitivity analysis for nonidentifiable parameters. To reduce the effects of nonidentifiable parameters, we project the parameters to a lower dimensional space and we allow the reduced set of parameters to share a common distribution. We use the griddy Gibbs sampler to fit our models and compute DIC and BPP for model diagnostics. We illustrate our method using data from NHANES III data to obtain the finite population proportions.

A comparative study in Bayesian semiparametric approach to small area estimation

  • Heo, Simyoung;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.5
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    • pp.1433-1441
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    • 2016
  • Small area model provides reliable and accurate estimations when the sample size is not sufficient. Our dataset has an inherent nonlinear pattern which signicantly affects our inference. In this case, we could consider semiparametric models such as truncated polynomial basis function and radial basis function. In this paper, we study four Bayesian semiparametric models for small areas to handle this point. Four small area models are based on two kinds of basis function and different knots positions. To evaluate the different estimates, four comparison measurements have been employed as criteria. In these comparison measurements, the truncated polynomial basis function with equal quantile knots has shown the best result. In Bayesian calculation, we use Gibbs sampler to solve the numerical problems.

Simultaneous modeling of mean and variance in small area estimation

  • Kim, Myungjin;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.5
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    • pp.1423-1431
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    • 2016
  • When the sample size in a certain domain is too small to produce adequate information, small area model with random effects is usually used. Also, if we do not consider an inherent pattern which data possess, it considerably affects inference. In this paper, we mainly focus on modeling to handle increased variation of the Current Population Survey (CPS) median income as the Internal Revenue Service (IRS) mean income increases. In a hierarchical Bayesian framework, most estimations are carried out through the Gibbs sampler while the grid method is used to generate parameters from non-standard form. Numerical study indicates that the performance of proposed model is better than that of CPS method in terms of four comparison measurements.

Classical and Bayesian studies for a new lifetime model in presence of type-II censoring

  • Goyal, Teena;Rai, Piyush K;Maury, Sandeep K
    • Communications for Statistical Applications and Methods
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    • v.26 no.4
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    • pp.385-410
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    • 2019
  • This paper proposes a new class of distribution using the concept of exponentiated of distribution function that provides a more flexible model to the baseline model. It also proposes a new lifetime distribution with different types of hazard rates such as decreasing, increasing and bathtub. After studying some basic statistical properties and parameter estimation procedure in case of complete sample observation, we have studied point and interval estimation procedures in presence of type-II censored samples under a classical as well as Bayesian paradigm. In the Bayesian paradigm, we considered a Gibbs sampler under Metropolis-Hasting for estimation under two different loss functions. After simulation studies, three different real datasets having various nature are considered for showing the suitability of the proposed model.

Semiparametric Bayesian multiple comparisons for Poisson Populations

  • Cho, Jang Sik;Kim, Dal Ho;Kang, Sang Gil
    • Communications for Statistical Applications and Methods
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    • v.8 no.2
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    • pp.427-434
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    • 2001
  • In this paper, we consider the nonparametric Bayesian approach to the multiple comparisons problem for I Poisson populations using Dirichlet process priors. We describe Gibbs sampling algorithm for calculating posterior probabilities for the hypotheses and calculate posterior probabilities for the hypotheses using Markov chain Monte Carlo. Also we provide a numerical example to illustrate the developed numerical technique.

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Bayesian small area estimations with measurement errors

  • Goo, You Mee;Kim, Dal Ho
    • Journal of the Korean Data and Information Science Society
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    • v.24 no.4
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    • pp.885-893
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    • 2013
  • This paper considers Bayes estimations of the small area means under Fay-Herriot model with measurement errors. We provide empirical Bayes predictors of small area means with the corresponding jackknifed mean squared prediction errors. Also we obtain hierarchical Bayes predictors and the corresponding posterior standard deviations using Gibbs sampling. Numerical studies are provided to illustrate our methods and compare their eciencies.

Bayesian Parameter Estimation of the Four-Parameter Gamma Distribution

  • Oh, Mi-Ra;Kim, Kyung-Sook;Cho, Wan-Hyun;Son, Young-Sook
    • Communications for Statistical Applications and Methods
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    • v.14 no.1
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    • pp.255-266
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    • 2007
  • A Bayesian estimation of the four-parameter gamma distribution is considered under the noninformative prior. The Bayesian estimators are obtained by the Gibbs sampling. The generation of the shape/power parameter and the power parameter in the Gibbs sampler is implemented using the adaptive rejection sampling algorithm of Gilks and Wild (1992). Also, the location parameter is generated using the adaptive rejection Metropolis sampling algorithm of Gilks, Best and Tan (1995). Finally, the simulation result is presented.

Bayesian analysis of cumulative logit models using the Monte Carlo Gibbs sampling (몬테칼로깁스표본기법을 이용한 누적로짓 모형의 베이지안 분석)

  • 오만숙
    • The Korean Journal of Applied Statistics
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    • v.10 no.1
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    • pp.151-161
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    • 1997
  • An easy Monte Carlo Gibbs sampling approach is suggested for Bayesian analysis of cumulative logit models for ordinal polytomous data. Because in the cumulative logit model the posterior conditional distributions of parameters are not given in convenient forms for random sample generation, appropriate latent variables are introduced into the model so that in the new model all the conditional distributions are given in very convenient forms for implementation of the Gibbs sampler.

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Bayesian Estimation of the Two-Parameter Kappa Distribution

  • Oh, Mi-Ra;Kim, Sun-Worl;Park, Jeong-Soo;Son, Young-Sook
    • Communications for Statistical Applications and Methods
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    • v.14 no.2
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    • pp.355-363
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    • 2007
  • In this paper a Bayesian estimation of the two-parameter kappa distribution was discussed under the noninformative prior. The Bayesian estimators are obtained by the Gibbs sampling. The generation of the shape parameter and scale parameter in the Gibbs sampler is implemented using the adaptive rejection Metropolis sampling algorithm of Gilks et al. (1995). A Monte Carlo study showed that the Bayesian estimators proposed outperform other estimators in the sense of mean squared error.

Bayesian Analysis of Multivariate Threshold Animal Models Using Gibbs Sampling

  • Lee, Seung-Chun;Lee, Deukhwan
    • Journal of the Korean Statistical Society
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    • v.31 no.2
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    • pp.177-198
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    • 2002
  • The estimation of variance components or variance ratios in linear model is an important issue in plant or animal breeding fields, and various estimation methods have been devised to estimate variance components or variance ratios. However, many traits of economic importance in those fields are observed as dichotomous or polychotomous outcomes. The usual estimation methods might not be appropriate for these cases. Recently threshold linear model is considered as an important tool to analyze discrete traits specially in animal breeding field. In this note, we consider a hierarchical Bayesian method for the threshold animal model. Gibbs sampler for making full Bayesian inferences about random effects as well as fixed effects is described to analyze jointly discrete traits and continuous traits. Numerical example of the model with two discrete ordered categorical traits, calving ease of calves from born by heifer and calving ease of calf from born by cow, and one normally distributed trait, birth weight, is provided.