• Title/Summary/Keyword: hierarchical estimation

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Hierarchical Bayes Estimation of Parameter and Reliability Function in Doubly Censored Exponential Distribution (양쪽중단된 지수분포의 모수와 신뢰도에 대한 계층적 베이즈추정)

  • 조장식;강상길
    • The Korean Journal of Applied Statistics
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    • v.12 no.2
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    • pp.405-414
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    • 1999
  • 양쪽중단(doubly censored)된 지수분포에서 모수와 신뢰도함수를 계층적 베이지안(hierarchical Bayesian)방법을 이용하여 추정하였다. 베이즈 계산은 깁스표본기법(Gibbs sampler)을 이용하고 또한 완전조건부 분포(full conditional distribution)의 정량화 상수를 모르는 경우에는 적합기각방법(adaptive rejection sampling)을 이용하였다. 그리고 실제자료를 이용하여 분석을 하였다.

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Sampling Based Approach to Hierarchical Bayesian Estimation of Reliability Function

  • Younshik Chung
    • Communications for Statistical Applications and Methods
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    • v.2 no.2
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    • pp.43-51
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    • 1995
  • For the stress-strengh function, hierarchical Bayes estimations considered under squared error loss and entropy loss. In particular, the desired marginal postrior densities ate obtained via Gibbs sampler, an iterative Monte Carlo method, and Normal approximation (by Delta method). A simulation is presented.

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Small area estimation of the insurance benefit for customer segmentations (고객집단별 보험금에 대한 소지역 추정)

  • Kim, Yeong-Hwa;Kim, Ki-Su
    • Journal of the Korean Data and Information Science Society
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    • v.20 no.1
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    • pp.77-87
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    • 2009
  • Bayesian methods have been focused in recent years for solving small area estimation problems. In this paper, the hierarchical Bayes procedure is implemented via MCMC techniques and compared with the results of One-way, GLM-Normal, and GLM-Gamma cases by analyzing real data of insurance benefit for customer segmentations. After analyzing insurance benefit real data for customer segmentations, we can conclude that the insurance benefit estimator through the small area estimation is more efficient than the estimators by other methods. In addition, we found that the small area estimation gave accurate estimation result for the small number domains.

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Joint Blind Parameter Estimation of Non-cooperative High-Order Modulated PCMA Signals

  • Guo, Yiming;Peng, Hua;Fu, Jun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.10
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    • pp.4873-4888
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    • 2018
  • A joint blind parameter estimation algorithm based on minimum channel stability function aimed at the non-cooperative high-order modulated paired carrier multiple access (PCMA) signals is proposed. The method, which uses hierarchical search to estimate time delay, amplitude and frequency offset and the estimation of phase offset, including finite ambiguity, is presented simultaneously based on the derivation of the channel stability function. In this work, the structure of hierarchical iterative processing is used to enhance the performance of the algorithm, and the improved algorithm is used to reduce complexity. Compared with existing data-aided algorithms, this algorithm does not require a priori information. Therefore, it has significant advantage in solving the problem of blind parameter estimation of non-cooperative high-order modulated PCMA signals. Simulation results show the performance of the proposed algorithm is similar to the modified Cramer-Rao bound (MCRB) when the signal-to-noise ratio is larger than 16 dB. The simulation results also verify the practicality of the proposed algorithm.

Multi-Finger 3D Landmark Detection using Bi-Directional Hierarchical Regression

  • Choi, Jaesung;Lee, Minkyu;Lee, Sangyoun
    • Journal of International Society for Simulation Surgery
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    • v.3 no.1
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    • pp.9-11
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    • 2016
  • Purpose In this paper we proposed bi-directional hierarchical regression for accurate human finger landmark detection with only using depth information.Materials and Methods Our algorithm consisted of two different step, initialization and landmark estimation. To detect initial landmark, we used difference of random pixel pair as the feature descriptor. After initialization, 16 landmarks were estimated using cascaded regression methods. To improve accuracy and stability, we proposed bi-directional hierarchical structure.Results In our experiments, the ICVL database were used for evaluation. According to our experimental results, accuracy and stability increased when applying bi-directional hierarchical regression more than typical method on the test set. Especially, errors of each finger tips of hierarchical case significantly decreased more than other methods.Conclusion Our results proved that our proposed method improved accuracy and stability and also could be applied to a large range of applications such as augmented reality and simulation surgery.

HIERARCHICAL ERROR ESTIMATORS FOR LOWEST-ORDER MIXED FINITE ELEMENT METHODS

  • Kim, Kwang-Yeon
    • Korean Journal of Mathematics
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    • v.22 no.3
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    • pp.429-441
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    • 2014
  • In this work we study two a posteriori error estimators of hierarchical type for lowest-order mixed finite element methods. One estimator is computed by solving a global defect problem based on the splitting of the lowest-order Brezzi-Douglas-Marini space, and the other estimator is locally computable by applying the standard localization to the first estimator. We establish the reliability and efficiency of both estimators by comparing them with the standard residual estimator. In addition, it is shown that the error estimator based on the global defect problem is asymptotically exact under suitable conditions.

On the Performance of Empiricla Bayes Simultaneous Interval Estimates for All Pairwise Comparisons

  • Kim, Woo-Chul;Han, Kyung-Soo
    • Journal of the Korean Statistical Society
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    • v.24 no.1
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    • pp.161-181
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    • 1995
  • The goal of this article is to study the performances of various empirical Bayes simultaneous interval estimates for all pairwise comparisons. The considered empirical Bayes interval estimaters are those based on unbiased estimate, a hierarchical Bayes estimate and a constrained hierarchical Bayes estimate. Simulation results for small sample cases are given and an illustrative example is also provided.

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Motion Estimation using Hierarchical Triangular Mesh and Fast Node Convergence (계층적 삼각형 메쉬를 이용한 움직임 추정과 노드의 수렴 고속화)

  • 이동규;이두수
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.17 no.2
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    • pp.88-94
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    • 2003
  • In this paper, we propose a hierarchical triangular mesh generation method based on the motion information and a fast rude convergence method. From the variance of Image difference we decide the region that subdivision is required and perform the adequate triangulation method that is possible to yield a successive hierarchical triangulation. For fast node convergence, in initial search, we use the refinement method that separate the backgroung and object region and maintain the mesh connection by using the bilinear interpolation. The simulation result demonstrate that proposed triangulation method have performance in PSNR than the conventional BMA or order mesh based method and refinement is appropriate for the case of the mesh size is small.

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.

A Fast Block Matching Algorithm Using Hierarchical Search Point Sampling (계층적인 탐색점 추출을 이용한 고속 블록 정합 알고리즘)

  • 정수목
    • Journal of the Korea Computer Industry Society
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    • v.4 no.12
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    • pp.1043-1052
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    • 2003
  • In this paper, we present a fast motion estimation algorithm to reduce the computations of block matching algorithm for motion estimation in video coding. The proposed algorithm is based on Multi-level Successive Elimination Algorithm and Efficient Multi-level Successive Elimination Algorithms. The best estimate of the motion vectors can be obtained by hierarchical search point sampling and thus the proposed algorithm can decrease the number of matching evaluations that require very intensive computations. The efficiency of the proposed algorithm was verified by experimental results.

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