• 제목/요약/키워드: Censored observations

검색결과 40건 처리시간 0.026초

Mixtures of Beta Processes Priors for Right Censored Survival Data

  • Kim, Yongdai
    • Journal of the Korean Statistical Society
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    • 제30권1호
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    • pp.127-138
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    • 2001
  • In order to combine parametric and nonparametric approaches together for survival analysis with censored observations, a new class of priors called mixtures of the beta processes is introduced. It is shown that mixtures of beta processes priors generalized the well known priors - mixtures of Dirichlet processes, and they are conjugate with right censored observations. Formulas for computing the posterior distribution are derived. Finally, a real data set is analyzed for illustrational purpose.

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A Study on Estimating Mean Lifetime After Modifying Censored Observations

  • Kim, Jinh-eum;Kim, Jee-hoon
    • 품질경영학회지
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    • 제26권1호
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    • pp.161-171
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    • 1998
  • Kim and Kim (1997) developed a method of estimating the mean lifetime based on the augmented data after imputing censored observations. Assuming the linear relationship between lifetime and covariates, and then introducing the procedure of Buckley and James (1979) to estimate the mean lifetimes of censored observations, they proposed a mean lifetime estimator and its consistency under the regularity conditions. In this article, the Kim and Kim's estimator is compared with the estimator introduced by Gill (1983) through simulations under the various configurations. Also, their estimator is illustrated with two real data sets.

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A study on the scores for right censored data

  • 박효일
    • 한국신뢰성학회:학술대회논문집
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    • 한국신뢰성학회 2000년도 추계학술대회
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    • pp.363-363
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    • 2000
  • We derive an asymptotic relation between the scores for the censored and uncensored observations for the untied value case among uncensored observations. With this relation, we show that two types of the linear rank statistics which are based on any consistent estimates of the distribution function, are asymptotically equivalent. Also, we discuss another asymptotic equivalence considered by Cuzick (1985).

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ESTIMATING MOMENTS OF THE SURVIVAL TIME FROM CENSORED OBSERVATIONS

  • Jung, In-Ha;Lee, Kang-Sup
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제2권2호
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    • pp.83-89
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    • 1995
  • A Bayes estimator of the survival distribution function due to Susarla and Van Ryzin(1976) is used to estimate the mth moment of a survival time on the basis of censored observations in a random censorship model. Asymptotic normality of the estimator is proved using the functional version of the delta method.

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Bayesian Prediction Analysis for the Exponential Model Under the Censored Sample with Incomplete Information

  • 김영훈;고정환
    • Journal of the Korean Data and Information Science Society
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    • 제13권1호
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    • pp.139-145
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    • 2002
  • This paper deals with the problem of obtaining the Bayesian predictive density function and the prediction intervals for a future observation and the p-th order statistics of n future observations for the exponential model under the censored sampling with incomplete information.

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REGRESSION WITH CENSORED DATA BY LEAST SQUARES SUPPORT VECTOR MACHINE

  • Kim, Dae-Hak;Shim, Joo-Yong;Oh, Kwang-Sik
    • Journal of the Korean Statistical Society
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    • 제33권1호
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    • pp.25-34
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    • 2004
  • In this paper we propose a prediction method on the regression model with randomly censored observations of the training data set. The least squares support vector machine regression is applied for the regression function prediction by incorporating the weights assessed upon each observation in the optimization problem. Numerical examples are given to show the performance of the proposed prediction method.

Estimation of the Exponential Distributions based on Multiply Progressive Type II Censored Sample

  • Lee, Kyeong-Jun;Park, Chan-Keun;Cho, Young-Seuk
    • Communications for Statistical Applications and Methods
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    • 제19권5호
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    • pp.697-704
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    • 2012
  • The maximum likelihood(ML) estimation of the scale parameters of an exponential distribution based on progressive Type II censored samples is given. The sample is multiply censored (some middle observations being censored); however, the ML method does not admit explicit solutions. In this paper, we propose multiply progressive Type II censoring. This paper presents the statistical inference on the scale parameter for the exponential distribution when samples are multiply progressive Type II censoring. The scale parameter is estimated by approximate ML methods that use two different Taylor series expansion types ($AMLE_I$, $AMLE_{II}$). We also obtain the maximum likelihood estimator(MLE) of the scale parameter under the proposed multiply progressive Type II censored samples. We compare the estimators in the sense of the mean square error(MSE). The simulation procedure is repeated 10,000 times for the sample size n = 20 and 40 and various censored schemes. The $AMLE_{II}$ is better than MLE and $AMLE_I$ in the sense of the MSE.

중도절단된 자료에 대한 가법회귀모형 (Additive Regression Models for Censored Data)

  • 김철기
    • 품질경영학회지
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    • 제24권1호
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    • pp.32-43
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    • 1996
  • In this paper we develop nonparametric methods for regression analysis when the response variable is subject to censoring that arises naturally in quality engineering. This development is based on a general missing information principle that enables us to apply, via an iterative scheme, nonparametric regression techniques for complete data to iteratively reconstructed data from a given sample with censored observations. In particular, additive regression models are extended to right-censored data. This nonparametric regression method is applied to a simulated data set and the estimated smooth functions provide insights into the relationship between failure time and explanatory variables in the data.

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Kernel Ridge Regression with Randomly Right Censored Data

  • Shim, Joo-Yong;Seok, Kyung-Ha
    • Communications for Statistical Applications and Methods
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    • 제15권2호
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    • pp.205-211
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    • 2008
  • This paper deals with the estimations of kernel ridge regression when the responses are subject to randomly right censoring. The iterative reweighted least squares(IRWLS) procedure is employed to treat censored observations. The hyperparameters of model which affect the performance of the proposed procedure are selected by a generalized cross validation(GCV) function. Experimental results are then presented which indicate the performance of the proposed procedure.

Weighted LS-SVM Regression for Right Censored Data

  • Kim, Dae-Hak;Jeong, Hyeong-Chul
    • Communications for Statistical Applications and Methods
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    • 제13권3호
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    • pp.765-776
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    • 2006
  • In this paper we propose an estimation method on the regression model with randomly censored observations of the training data set. The weighted least squares support vector machine regression is applied for the regression function estimation by incorporating the weights assessed upon each observation in the optimization problem. Numerical examples are given to show the performance of the proposed estimation method.