• Title/Summary/Keyword: Goodness

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Goodness of Fit Tests of Cox's Proportional Hazards Model

  • Song, Hae-Hiang;Lee, Sun-Ho
    • Journal of the Korean Statistical Society
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    • v.23 no.2
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    • pp.379-402
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    • 1994
  • Graphical and numerical methods for checking the assumption of proportional hazards of Cox model for censored survival data are discussed. The strenths and weaknessess of several goodness of fit tests for the propotional hazards for the two-sample problem are evaluated with Monte Carlo simulations, and the tests of Schoenfeld (1980), Andersen (1982), Wei (1984), and Gill and Schumacher (1987) are considered. The goodness of fit methods are illustrated with the survival data of patients who had chronic liver disease and had been treated with the endoscopy injection sclerotheraphy. Two other examples of data known to have nonpropotional hazards are also used in the illustration.

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A Goodness of Fit Tests Based on the Partial Kullback-Leibler Information with the Type II Censored Data

  • Park, Sang-Un;Lim, Jong-Gun
    • Proceedings of the Korean Statistical Society Conference
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    • 2003.10a
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    • pp.233-238
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    • 2003
  • Goodness of fit test statistics based on the information discrepancy have been shown to perform very well (Vasicek 1976, Dudewicz and van der Meulen 1981, Chandra et al 1982, Gohkale 1983, Arizona and Ohta 1989, Ebrahimi et al 1992, etc). Although the test is well defined for the non-censored case, censored case has not been discussed in the literature. Therefore we consider a goodness of fit test based on the partial Kullback-Leibler(KL) information with the type II censored data. We derive the partial KL information of the null distribution function and a nonparametric distribution function, and establish a goodness of fit test statistic. We consider the exponential and normal distributions and made Monte Calro simulations to compare the test statistics with some existing tests.

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Goodness-of-Fit Tests for the Ordinal Response Models with Misspecified Links

  • Jeong, Kwang-Mo;Lee, Hyun-Yung
    • Communications for Statistical Applications and Methods
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    • v.16 no.4
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    • pp.697-705
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    • 2009
  • The Pearson chi-squared statistic or the deviance statistic is widely used in assessing the goodness-of-fit of the generalized linear models. But these statistics are not proper in the situation of continuous explanatory variables which results in the sparseness of cell frequencies. We propose a goodness-of-fit test statistic for the cumulative logit models with ordinal responses. We consider the grouping of a dataset based on the ordinal scores obtained by fitting the assumed model. We propose the Pearson chi-squared type test statistic, which is obtained from the cross-classified table formed by the subgroups of ordinal scores and the response categories. Because the limiting distribution of the chi-squared type statistic is intractable we suggest the parametric bootstrap testing procedure to approximate the distribution of the proposed test statistic.

Comparison of Powers in Goodness of Fit Test of Quadratic Measurement Error Model

  • Moon, Myung-Sang
    • Communications for Statistical Applications and Methods
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    • v.9 no.1
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    • pp.229-240
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    • 2002
  • Whether to use linear or quadratic model in the analysis of regression data is one of the important problems in classical regression model and measurement error model (MEM). In MEM, four goodness of fit test statistics are available In solving that problem. Two are from the derivation of estimators of quadratic MEM, and one is from that of the general $k^{th}$-order polynomial MEM. The fourth one is derived as a variation of goodness of fit test statistic used in linear MEM. The purpose of this paper is to find the most powerful test statistic among them through the small-scale simulation.

A Goodness of Fit Approach to Major Lifetesting Problems

  • Ahmad, Ibrahim A.;Alwasel, Ibrahim A.;Mugdadi, A.R.
    • International Journal of Reliability and Applications
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    • v.2 no.2
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    • pp.81-97
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    • 2001
  • Lifetesting problems have been the subject of investigations for over three decades. Most suggested approaches are markedly different from those used in the related but wider goodness of fit problems. In the current investigation, it is demonstrated that a goodness of fit approach is possible in many lifetesting problems and that It results in simpler procedures that are asymptotically equivalent or better than standard ones. They may also have superior finite sample behavior. Several perennial classes are addressed here. The class of increasing failure rate (IFR) and the class of new better than used (NBU) are addressed first. In addition, we provide testing for a newer and practical class of new better than used in convex ordering (NBUC) due to Cao and Wang (1991). Other classes can be developed similarly and this point is illustrated with the classes of new better than used in expectation (NBUE) and harmonic new better than used in expectation (HNBUE).

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Goodness-of-fit tests based on generalized Lorenz curve for progressively Type II censored data from a location-scale distributions

  • Lee, Wonhee;Lee, Kyeongjun
    • Communications for Statistical Applications and Methods
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    • v.26 no.2
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    • pp.191-203
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    • 2019
  • The problem of examining how well an assumed distribution fits the data of a sample is of significant and must be examined prior to any inferential process. The observed failure time data of items are often not wholly available in reliability and life-testing studies. Lowering the expense and period associated with tests is important in statistical tests with censored data. Goodness-of-fit tests for perfect data can no longer be used when the observed failure time data are progressive Type II censored (PC) data. Therefore, we propose goodness-of-fit test statistics and a graphical method based on generalized Lorenz curve for PC data from a location-scale distribution. The power of the proposed tests is then assessed through Monte Carlo simulations. Finally, we analyzed two real data set for illustrative purposes.

A Study on the Saint Notion of Mencius (맹자(孟子)의 성인관(聖人觀) 연구(硏究))

  • Cho, Won-il
    • The Journal of Korean Philosophical History
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    • no.35
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    • pp.335-359
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    • 2012
  • The Mencius's saint is not a rational being but a being of real world. He thought that all mankind have the goodness, and if we complete it, we can become a 'saint' like the 'King Yao' or the 'King Shun'. And he maintained that to complete the goodness, we must understand what the goodness is. He has divided this knowledge into the innate phase and the acquired phase, and then insisted that mankind can be a saint by the both of them. Also, Mencius suggested that we can be saint by the preservation of goodness('Ren & Li'). To bring up the goodness, we're not supposed to be inclined to a material desire, we're asked a mental training of 'Si chemg' reflecting on them-self. It is a 'Dao' of the mankind. When it completes, mankind will commune(communicate) with nature. This paper focused the Saint notion of Mencius, especially the mental training of Saint & the social realization.

A Study on the Educational methods of Communication through Chinese classics -- focused on the concept of "Goodness" in Daehak-- (중국 고전을 활용한 커뮤니케이션 교육방안 연구 --대학(大學)속 선(善)을 중심으로 --)

  • Jung, In-Suk
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.1
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    • pp.461-468
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    • 2021
  • The Chinese classic 'The Great Learning' presents a guideline in which direction we should go for the character education and the realization of a just society. It conveys the message, 'Everyone must remain at the level of goodness for our community based on training our own mind and body.' Goodness is a generic concept that means universal truth in the right direction. This study aims to present the direction of communication education for how everyone should stay in goodness. Communication education about goodness could be conducted as follows. Based on the theory of interpersonal communication and persuasive communication, first the abstract concept of goodness is understood, brainstorming and schema activity for the good are performed for true communication, and then the teaching and learning method combining debate, flipped learning, and writing could be utilized. It is difficult to provide communication education with the message of goodness with students who have grown up on the basis of comparatively cramming education. However, through communication using discussion, a paradigm shift in education will take place, and it will not only help form human relationships, but also recognize the importance of the meaning of the community in the society in which we live, and ultimately it will help foster character.

The development of the argument about reality and painstaking in Wangyangming's Four-Sentence Teaching -around 'no Goodness and Badness' (양명 사구교 해석을 둘러싼 본체·공부 논쟁의 전개과정 - '무선무악심지체' 해석을 중심으로 -)

  • Lim, HongTae
    • The Journal of Korean Philosophical History
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    • no.28
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    • pp.417-445
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    • 2010
  • There are a few changes about Wangshouren's main tenet during the process of giving lectures. because of the reason that Wangshouren give lectures changed to different disciples, so every student had his different opinion and comprehension do Wangshouren's learning, which is the main reason that Wangshouren's disciples had occurred a difference. In the thinking field of later-Ming, there had occurred a furious argument surrounding the problem of "the Heart is no Goodness and Badness or not", and how to cure the harm of the Xinxue also had become a key issue to the two sides of argument. The donglin school that Guxiancheng was its delegates made a contest with the Xinxue's scholars that Zhourudeng and Guanzhidao were that delegates, which evolved surrounding that issue that "the nature is Good" and "the Heart no Goodness and Badness". In these arguments, the two sides often persist on their own opinions, but hadn't a right understanding for Wangshouren's original meaning. Liujishan and Huanglizhou thought that the meaning of the words "the Heart no Goodness and Badness" was that the Heart have no the intention of Goodness and Badness, not that the Nature was no Goodness and no Badness. So that the opinion of "the Heart no Goodness and Badness" was not the main idea of Wangshouren. Wangji hadn't got the whole meaning of the Four Sentences. Liujishan and Huanglizhou wanted to make a new explaination to Wangshouren's ideas according to literatures and theory.