• 제목/요약/키워드: confidence intervals

검색결과 1,096건 처리시간 0.031초

Constructing Simultaneous Confidence Intervals for the Difference of Proportions from Multivariate Binomial Distributions

  • Jeong, Hyeong-Chul;Kim, Dae-Hak
    • 응용통계연구
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    • 제22권1호
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    • pp.129-140
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    • 2009
  • In this paper, we consider simultaneous confidence intervals for the difference of proportions between two groups taken from multivariate binomial distributions in a nonparametric way. We briefly discuss the construction of simultaneous confidence intervals using the method of adjusting the p-values in multiple tests. The features of bootstrap simultaneous confidence intervals using non-pooled samples are presented. We also compute confidence intervals from the adjusted p-values of multiple tests in the Westfall (1985) style based on a pooled sample. The average coverage probabilities of the bootstrap simultaneous confidence intervals are compared with those of the Bonferroni simultaneous confidence intervals and the Sidak simultaneous confidence intervals. Finally, we give an example that shows how the proposed bootstrap simultaneous confidence intervals can be utilized through data analysis.

A Comparison Study for the Confidence Intervals of the Common Odds Ratio in the Stratified 2 X 2 Tables Using the Average Coverage Probability

  • Kwak, Min Jung;Jeong, Hyeong Chul
    • Communications for Statistical Applications and Methods
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    • 제10권3호
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    • pp.779-793
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    • 2003
  • In this paper, various methods for finding confidence intervals for common odds ratio $\psi$ of the K 2${\times}$2 tables are reviewed. Also we propose two jackknife confidence intervals and bootstrap confidence intervals for $\psi$. These confidence intervals are compared with the other existing confidence intervals by using Monte Carlo simulation with respect to the average coverage probability.

A Comparison of Some Approximate Confidence Intervals for he Poisson Parameter

  • Kim, Daehak;Jeong, Hyeong-Chul
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.899-911
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    • 2000
  • In this paper, we reviewed thirteen methods for finding confidence intervals for he mean of poisson distribution. Bootstrap confidence intervals are also introduced. Two bootstrap confidence intervals are compared with the other existing eleven confidence intervals by using Monte Carlo simulation with respect to the average coverage probability of Woodroofe and Jhun (1989).

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Interval Estimations for Reliablility in Stress-Strength Model by Bootstrap Method

  • Lee, In-Suk;Cho, Jang-Sik
    • Journal of the Korean Data and Information Science Society
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    • 제6권1호
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    • pp.73-83
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    • 1995
  • We construct the approximate bootstrap confidence intervals for reliability (R) when the distributions of strength and stress are both normal. Also we propose percentile, bias correct (BC), bias correct acceleration (BCa), and percentile-t intervals for R. We compare with the accuracy of the proposed bootstrap confidence intervals and classical confidence interval based on asymptotic normal distribution through Monte Carlo simulation. Results indicate that the confidence intervals by bootstrap method work better than classical confidence interval. In particular, confidence intervals by BC and BCa method work well for small sample and/or large value of true reliability.

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EDF 기대손실에 기초한 공정능력지수의 붓스트랩 신뢰구간 (Bootstrap Confidence Intervals of the Process Capability Index Based on the EDF Expected Loss)

  • 임태진;송현석
    • 품질경영학회지
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    • 제31권4호
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    • pp.164-175
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    • 2003
  • This paper investigates bootstrap confidence intervals of the process capability index(PCI) based on the expected loss derived from the empirical distribution function(EDF). The PCI based on the expected loss is too complex to derive its confidence interval analytically, so the bootstrap method is a good alternative. We propose three types of the bootstrap confidence interval; the standard bootstrap(SB), the percentile bootstrap(PB), and the acceleration biased­corrected percentile bootstrap(ABC). We also perform a comprehensive simulation study under various process distributions, in order to compare the accuracy of the coverage probability of the bootstrap confidence intervals. In most cases, the coverage probabilities of the bootstrap confidence intervals from the EDF PCI turned out to be more accurate than those from the PCI based on the normal distribution. It is expected that the bootstrap confidence intervals from the EDF PCI can be utilized in real processes where the true distribution family may not be known.

신뢰도와 신뢰수준을 고려한 기대수명 공차구간 설정에 관한 연구 (Tolerance Intervals for Expected Time at the Given Reliability and Confidence Level)

  • 최성운
    • 대한안전경영과학회지
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    • 제7권2호
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    • pp.73-83
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    • 2005
  • This paper is to propose tolerance intervals for expected time at the given reliability and confidence level for continuous and discrete reliability model. We consider guaranteed - coverage tolerance intervals, that is, reliability - confidence level tolerance intervals. These proposed methodologies can be applied to any industrial application where the customer's operating specification require a high level of reliability.

Bootstrap and Delete-d Jackknife Confidence Intervals for Parameters of an Exponential Distribution

  • Kang, Suk-Bok;Cho, Young-Suk
    • Journal of the Korean Data and Information Science Society
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    • 제8권1호
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    • pp.59-70
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    • 1997
  • We introduce several estimators of the location and the scale parameters of the two-parameter exponential distribution, and then compare these estimators by the mean square error (MSE). Using the parametric bootstrap estimators and the delete-d jackknife, we obtain the bootstrap and the delete-d jackknife confidence intervals for the location and the scale parameters and compare the bootstrap confidence intervals with the delete-d jackknife confidence intervals by length and coverage probability through Monte Carlo method.

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Bootstrap Confidence Intervals for Reliability in 1-way ANOVA Random Model

  • Dal Ho Kim;Jang Sik Cho
    • Communications for Statistical Applications and Methods
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    • 제3권1호
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    • pp.87-99
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    • 1996
  • We construct bootstrap confidence intervals for reliability, R= P{X>Y}, where X and Y are independent normal random variables. One way ANOVA random effect models are assumed for the populations of X and Y, where standard deviations $\sigma_{x}$ and $\sigma_{y}$ are unequal. We investigate the accuracy of the proposed bootstrap confidence intervals and classical confidence intervals work better than classical confidence interval for small sample and/or large value of R.

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CONFIDENCE INTERVALS ON THE AMONG GROUP VARIANCE COMPONENT IN A REGRESSION MODEL WITH AN UNBALANCED ONE-FOLD NESTED ERROR STRUCTURE

  • 박동준
    • 한국통계학회:학술대회논문집
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    • 한국통계학회 2002년도 추계 학술발표회 논문집
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    • pp.141-146
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    • 2002
  • In this article we consider the problem of constructing confidence intervals for a linear regression model with nested error structure. A popular approach is the likelihood-based method employed by PROC MIXED of SAS. In this paper, we examine the ability of MIXED to produce confidence intervals that maintain the stated confidence coefficient. Our results suggest the intervals for the regression coefficients work well, but the intervals for the variance component associated with the primary level cannot be recommended. Accordingly, we propose alternative methods for constructing confidence intervals on the primary level variance component. Computer simulation is used to compare the proposed methods. A numerical example and SAS code are provided to demonstrate the methods.

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Comparison of the Kaplan-Meier and Nelson Estimators using Bootstrap Confidence Intervals

  • Cha, Young Joon;Lee, Jae Man
    • 품질경영학회지
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    • 제23권4호
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    • pp.42-51
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    • 1995
  • The bootstrap confidence intervals are a computer-based method for assigning measures of accuracy to statistical estimators. In this paper we examine the small sample behavior of the Kaplan-Meier and Nelson-type estimators for the survival function using the bootstrap and asymptotic normal-theory confidence intervals. The Nelson-type estimator is nearly always better than the Kaplan-Meier estimator in the sense of achieved error rates. From the point of confidence length, the reverse is true. Also, we show that the bootstrap confidence intervals are better than the asymptotic normal-theory confidence intervals in terms of achieved error rates and confidence length.

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