• 제목/요약/키워드: goodness of fit test

검색결과 425건 처리시간 0.026초

GFRP 보강근과 콘크리트 사이의 부착모델에 관한 고찰 (Bond Models for GFRP Rebar Embedded in Concrete)

  • 유영준;박지선;박영환;김형열
    • 한국구조물진단유지관리공학회 논문집
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    • 제10권3호
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    • pp.143-151
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    • 2006
  • 본 논문은 철근 또는 GFRP 보강근과 콘크리트 사이의 해석적 부착모델에 관한 적합성에 대해 기술하였다. 부착시편은 CSA 규준에 따라 제작하여 실험하였으며, 실험에 사용된 보강근의 종류는 철근과 상용화된 GFRP 보강근 2종(ASLAN, ISOROD)이다. 실험결과를 이용하여 새로운 부착모델을 제안하였으며, 기존 연구자들이 제안한 해석적 부착모델과 새롭게 제안된 부착모델의 적합성을 최소자승법을 통해 검토하였다. 검토결과 새롭게 제안된 해석적 부착모델은 기존 부착모델에 비해 높은 적합성을 나타내었다.

Testing Goodness of Fit in Nonparametric Function Estimation Techniques for Proportional Hazards Model

  • Kim, Jong-Tae
    • Communications for Statistical Applications and Methods
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    • 제4권2호
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    • pp.435-444
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    • 1997
  • The objective of this study is to investigate the problem of goodness of fit testing based on nonparametric function estimation techniques for the random censorship model. The small and large sample properties of the proposed test, $E_{mn}$, were investigated and it is shown that under the proportional hazard model $E_{mn}$ has higher power compared to the powers of the Kolmogorov -Smirnov, Kuiper, Cramer-von Mises, and analogue of the Cramer-von Mises type test statistic.

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Testing Goodness-of-Fit for No Effect Models

  • Sungho Lee;Jongtae Kim;GyoungAe Moon
    • Communications for Statistical Applications and Methods
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    • 제5권3호
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    • pp.935-944
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    • 1998
  • This paper investigates the problem of goodness of fit tests for no effect model. The proposed test statistic $Z_{mn}$ is obtained by multiplying constant on the model free curve estimation techniques. The small and large sample properties of$Z_{mn}$ are investigated and the good results of power studies for the proposed test are illustrated.

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Goodness-of-fit Test for the Extreme Value Distribution Based on Multiply Type-II Censored Samples

  • Kang, Suk-Bok;Cho, Young-Seuk;Han, Jun-Tae
    • Journal of the Korean Data and Information Science Society
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    • 제19권4호
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    • pp.1441-1448
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    • 2008
  • We propose the modified quantile-quantile (Q-Q) plot using the approximate maximum likelihood estimators and the modified normalized sample Lorenz curve (NSLC) plot for the extreme value distribution based on multiply Type-II censored samples. Using two example data sets, we picture the modified Q-Q plot and the modified NSLC plot.

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Goodness-of-fit tests for randomly censored Weibull distributions with estimated parameters

  • Kim, Namhyun
    • Communications for Statistical Applications and Methods
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    • 제24권5호
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    • pp.519-531
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    • 2017
  • We consider goodness-of-fit test statistics for Weibull distributions when data are randomly censored and the parameters are unknown. Koziol and Green (Biometrika, 63, 465-474, 1976) proposed the $Cram\acute{e}r$-von Mises statistic's randomly censored version for a simple hypothesis based on the Kaplan-Meier product limit of the distribution function. We apply their idea to the other statistics based on the empirical distribution function such as the Kolmogorov-Smirnov and Liao and Shimokawa (Journal of Statistical Computation and Simulation, 64, 23-48, 1999) statistics. The latter is a hybrid of the Kolmogorov-Smirnov, $Cram\acute{e}r$-von Mises, and Anderson-Darling statistics. These statistics as well as the Koziol-Green statistic are considered as test statistics for randomly censored Weibull distributions with estimated parameters. The null distributions depend on the estimation method since the test statistics are not distribution free when the parameters are estimated. Maximum likelihood estimation and the graphical plotting method with the least squares are considered for parameter estimation. A simulation study enables the Liao-Shimokawa statistic to show a relatively high power in many alternatives; however, the null distribution heavily depends on the parameter estimation. Meanwhile, the Koziol-Green statistic provides moderate power and the null distribution does not significantly change upon the parameter estimation.

한국어판 수정된 스트레스 평가 도구(Revised Stress Appraisal Measure)의 타당도와 신뢰도 (Validity and Reliability of Korean Version of the Revised Stress Appraisal Measure (RSAM))

  • 김정선;김계하;강현철
    • 한국콘텐츠학회논문지
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    • 제15권3호
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    • pp.290-302
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    • 2015
  • 본 연구의 목적은 대학생들을 대상으로 수정된 스트레스 평가 도구(Revised Stress Appraisal Measure, RSAM)를 우리나라 실정에 맞게 번역하고, 타당도와 신뢰도를 검증하는 것이다. IBM SPSS Statistics 21과 AMOS 21 program을 이용하여 내적 일관성 신뢰도, 구성타당도, 준거타당도 검사를 하였다. 자료 수집은 G시와 C 지역 소재의 5개 대학교에 재학 중인 296명의 대학교 4학년 학생을 임의로 표출하였다. 한국어판 RSAM은 5개 요인으로 분류되었으며, 전체 변량은 68.4%를 설명하였다. 5개의 하위요인은 확증적 요인분석에 의해 타당성이 입증되었다(p<.001, Goodness of Fit Index, Adjusted Goodness of Fit Index, Normed Fit Index, Comparative Fit Index >.08, Root Mean Square Error of Approximation=.056). 준거타당도에서, 척도의 점수는 한국어판 Perceived Stress Scale (PSS)와 유의한 상관관계가 있었다. 신뢰도 계수는 .73에서 .89까지였다. 한국어판 RSAM 은 구성타당도와 준거타당도, 그리고 내적 일관성 신뢰도에서 만족할 만한 것으로 나타났다. 따라서 본 도구는 한국 대학생들의 스트레스 평가를 측정하는데 적합한 도구가 될 수 있을 것이다.

Turkish Version of the Perceived Future Decent Work Securement Scale: Validity and Reliability for Nursing Students

  • Oznur Ispir Demir;Betul Sonmez;Duygu Gul;Sergul Duygulu
    • Safety and Health at Work
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    • 제14권3호
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    • pp.332-339
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    • 2023
  • Background: The aim of the study was to test the validity and reliability of the Perceived Future Decent Work Securement Scale for Turkish nursing students. Methods: A cross-sectional, methodological study design was used. The study was carried out at three nursing undergraduate programs in Turkey during the academic year of 2020-2021 with 336 senior nursing students. Language validity and content validity analyses were performed for the scale adaptation, followed by confirmatory factor analysis (CFA) for construct validity. The reliability of the scale was determined using the test-retest and Cronbach's alpha internal consistency coefficient. Results: The scale-content validity index score was 0.988. In CFA, all goodness-of-fit indices verified the acceptable fit of the model; its root mean square error of approximation was 0.076; the normed fit index was 0.909; the standardized mean square residual was 0.097; the relative fit index was 0.881; the goodness-of-fit index was 0.915; the adjusted goodness-of-fit index was 0.872 and χ2/df = 2.932. The overall reliability was α = 0.86. The item-total correlations of the scale were above the acceptable level, and the test-retest analysis had a high correlation. The access to healthcare (14.68, SD 3.53) obtained the highest average score, and the adequate compensation (8.52, SD 3.76) was the lowest rated by the senior nursing students. Conclusion: The Perceived Future Decent Work Securement Scale is a valid and reliable scale to assess nursing students' future decent work securement.

Comparison of Parameter Estimation Methods in the Analysis of Multivariate Categorical Data with Logit Models

  • Song, Hae-Hiang
    • Journal of the Korean Statistical Society
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    • 제12권1호
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    • pp.24-35
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    • 1983
  • In fitting models to data, selection of the most desirable estimation method and determination of the adequacy of fitted model are the central issues. This paper compares the maximum likelihood estimators and the minimum logit chi-square estimators, both being best asymptotically normal, when logit models are fitted to infant mortality data. Chi-square goodness-of-fit test and likelihood ratio one are also compared. The analysis infant mortality data shows that the outlying observations do not necessarily result in the same impact on goodness-of-fit measures.

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마팅게일잔차에 기초한 가산위험모형의 적합도검정법 (A goodness-of-fit test based on Martinale residuals for the additive risk model)

  • 김진흠;이승연
    • 응용통계연구
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    • 제9권1호
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    • pp.75-89
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    • 1996
  • 본 논문에서는 하나의 이진공변량(binary covariate)을 갖는 가산위험모형(additive risk model)의 적합도를 검정하기 위한 검정법을 제안하였다. 제안된 검정법은 마팅게일잔차(martingale residual)에 기초한 Wei(1984)의 비례위험모형(proportional hazards model)의 적합도검정법을 가산위험모형으로 확장한 형태이다. 제안된 검정통계량의 점근성질을 유도하였고 실제자료에 적용하여 보았다.

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강우 지역빈도해석의 적용성 연구 (Study on Rainfall Regional Frequency Analysis)

  • 신홍준;남우성;허준행;김경덕
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.593-598
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    • 2005
  • At-site analysis is not appropriate if the record length is shorter than target return period T. If the record length is longer than 27 years, then at-site analysis may be sufficient(Institute of Hydrology, 1999). However, in such a case, regional frequency analysis is recommended for purpose of comparison. Record lengths of annual maximum rainfall data in Korea are usually shorter than 50 years. It is therefore essential to apply regional frequency analysis for estimating rainfall quantiles of more than 100 years return period. In this research, regional rainfall frequency analysis is performed for hourly rainfall data of South Korea. Homogeneous regions are idntified by clusgter analysis which is a standard method of statistical multivariate analysis for dividing a data set into groups. An appropriate distribution is chosen by goodness-of-fit test. GLO is found to be an appropriate distribution as a result of goodness-of-fit measure (Hosking & Wallis, 1997). Simulation experiments are performed to check the performance of frequency analysis techniques. The effects of discordant sites on quantiles are considered.

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