• Journal of the Korean Statistical Society
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• 제22권2호
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• pp.159-169
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• 1993

In this article, we consider two sample problem with randomly right censored data. We propse two-sample confidence intervals for the difference in medians or any quantiles, based on bootstrap. The bootstrap version of two-sample confidence intervals proposed in this article is simple to apply and do not need the assumption of the shift model, so that for the non-shift model, the density estimation is not necessary, which is an attractive feature in small to moderate sized sample case.

• Communications for Statistical Applications and Methods
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• 제9권1호
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• pp.281-289
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• 2002

In this paper, we considered an application of the bootstrap method for logit model. Estimation of type I error probability, the bootstrap p-values and bootstrap confidence intervals of parameter were proposed. Small sample Monte Carlo simulation were conducted in order to compare proposed method with existing normal theory based asymptotic method.

• Communications for Statistical Applications and Methods
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• 제7권3호
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• pp.859-869
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• 2000

In this paper, various methods for finding confidence intervals for p of binomial parameter are reviewed. Also we introduce tow bootstrap confidence intervals for p. We compare the performance of bootstrap methods with other methods in terms of average coverage probability by Monte Carlo simulation. Advantages of these bootstrap methods are discussed.

• Communications for Statistical Applications and Methods
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• 제12권2호
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• pp.521-529
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• 2005

In this paper, we consider a bootstrap method to the 'row and column effects model' (RC model) to analyze a contingency table with ordered variables. We propose a bootstrap procedure for testing of independence, equality of intervals, and goodness of fit in the RC model. A real data example is included.

• Communications for Statistical Applications and Methods
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• 제16권2호
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• pp.287-297
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• 2009

일반적으로 일반화 자기회귀 조건부 이분산(GARCH)모형 하에서, 우도함수에 기반한 자료의 예측구간의 추정은 오차항의 분포에 민감하게 반응하고 더욱이 조건부분산의 경우 구간추정이 현실적으로 쉽게 풀리지 않는 문제이다. 이를 해결하기 위해 붓스트랩방법(bootstrap method)이 적용될 수 있음을 최근 연구들을 통해 밝혀졌다. 본 논문에서는 GARCH모형 하에서 자료와 변동성(조건부 분산)의 예측구간 추정을 위해 최근 소개된 Pascual 등 (2006)의 논문을 토대로 붓스트랩 방법를 정리하였다 실제 사례분석을 위해 국내 주가수익률자료를 이용하였다.

• Communications for Statistical Applications and Methods
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• 제14권2호
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• pp.365-376
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• 2007

This research considers to propose the control charts using median for the location parameter. In order to decide the control limits, we apply several bootstrap methods through the approach obtaining the confidence interval except the standard bootstrap method. Then we illustrate our procedure using an example and compare the performance among the various bootstrap methods by obtaining the length between control limits through the simulation study. The standard bootstrap may be apt to yield shortest length while the bootstrap-t method, the longest one. Finally we comment briefly about some specific features as concluding remarks.

• 응용통계연구
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• 제7권2호
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• pp.269-277
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• 1994

최소카이제곱추정에 의하여 구한 추정량의 표본분포를 붓스트랩으로 근사시켰을 때에도 정규근사와 최소한 동등함을 설명하고, 이 이론을 자궁경부암 조직에서 검출되는 란게르한스 세포의 출현률 추정에 이용하였다. 란게르한스 세포의 출현횟수를 포지티브 포아송 모형에 적합시켰으며, 추정된 출현률의 표준오차는 대표본 근사 및 붓스트랩을 이용하여 계산하였다. 두 방법 모두 비슷한 결과를 제공하였다.

• Communications for Statistical Applications and Methods
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• 제4권3호
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• pp.917-927
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• 1997

Consider the confidence interval estimators of treatment effect when some of data to be analyzed are randomly censored, assuming two-sample location-shift model. Recently proposed PARK and PARK(1995) Estimators is discussed and a bootstrap estimator is proposed. This estimator is compared with other well-known estimators throught the simulation studies and recommendations about the use are made.

• 응용통계연구
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• 제15권2호
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• pp.355-366
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• 2002

범주형 자료의 구조파악에 주로 이용되는 로짓모형에서 비모수적 방법을 이용한 모수의 신뢰구간추정과 가설검정 등의 통계적 추론에 대하여 살펴보았다. 모수에 대한 통계적 추론에서 정규분포에 근거한 모수적 방법(Wald 방법)보다는 붓스트랩 방법이나 임의순열을 활용한 비모수적 방법이 많이 활용되고 있다. 본 연구에서는 로짓모형의 모수에 대한 비모수적 추론방법으로 붓스트랩(bootstrap)과 임의순열(random permutation)의 두 방법을 고려하고 모의실험을 통하여 가설검정의 검정력과 신뢰구간추정의 포함확률을 비교하였고 사례분석을 다루었다.

• Communications for Statistical Applications and Methods
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• 제8권1호
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• pp.127-135
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• 2001

In this paper, we consider a simple method for testing the assumption of independent censoring on the basis of a Cox proportional hazards regression model with a time-dependent covariate. This method involves a two-stage sampling in which a random subset of censored observations is selected and followed-up until their true survival times are observed. Lee and Wolfe(1998) proposed an adjusted estimate of the survivor function for the dependent censoring under a proportional hazards alternative. This paper extends their result to obtain a bootstrap confidence interval for the adjusted survivor function under the dependent censoring. The proposed procedure is illustrated with an example of a clinical trial for lung cancer analysed in Lee and Wolfe(1998).