• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.841-849
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• 2001

The influence in fitting an equicorrelation model is investigated using the influence function. The influence functions for the model parameters are derived and its sample versions are used for investigating the influence of observations on the estimators of the parameters. Some relationships among the sample versions are found. We will derive a measure for identifying observations that have a large influence on the test of fitting the equicorrelation model using the influence function method. An example is given for illustration.

• Communications for Statistical Applications and Methods
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• 제8권3호
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• pp.753-765
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• 2001

We suggest a quantitative conditional unrelated question model that can be used in obtaining more sensitive information. For whom say "yes" about the less 7han sensitive question .B we ask only about the more sensitive variable X. We extend our model to two sample case when there is no information about the true mean of the unrelated variable Y. Finally we compare the efficiency of our model with that of Greenberg et al.′s.

• Communications for Statistical Applications and Methods
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• 제6권2호
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• pp.511-522
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• 1999

The paper considers the problem of robustness in hierarchical bayesian models. In specific we address Bayesian robustness in the estimation of normal means. We provide the ranges of the posterior means under $\varepsilon$-contamination class as well as the density ratio class of priors. For the class of priors that are uniform over a specified interval we investigate the sensitivity as to the choice of the intervals. The methods are illustrated using the famous baseball data of Efron and Morris(1975).

• Communications for Statistical Applications and Methods
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• 제7권1호
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• pp.277-284
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• 2000

The transformed sample Lorenz curve provides a powerful and easily computed goodness-of-fit test for exponentiality which does not depend on the unknown scale parameter. We compare the power of the transformed sample Lorenz curve statistic with the other goodness-of-fit tests for exponentiality against various alternatives through Monte Carlo methods and discuss the results.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.746-754
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• 1996

Grading and sorting fresh cut flowers are time consuming process. In Korea, cut flowers are sorted mostly by human inspection due to the lack of adequate machinery. In this paper, quality evaluation factors of cut flowers are discussed, and types of sorting machines existing in the market are introduced . Aspects of computer image processing in evaluation the quality of cut flowers are also discussed.

• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.901-908
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• 1999

Using the Transformed Lorenz curve which is introduced by Cho et al.(1999) we propose the test statistic for testing of normality that is very important test in statistical analysis and compare the proposed test statistic with the Shapiro and Wilk's W test statistic in terms of the power of test through by Monte Carlo method.

• Communications for Statistical Applications and Methods
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• 제6권3호
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• pp.939-946
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• 1999

We propose methods for detecting influential observations that have a large influence on the likelihood ratio test statistic for the multivariate Behrens-Fisher problem. For this purpose we derive the influence curve and the derivative influence of the likelihood ratio test statistic. An illustrative example is given to show the effectiveness of the proposed methods on the identification of influential observations.

• Communications for Statistical Applications and Methods
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• 제3권2호
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• pp.169-174
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• 1996

In the present paper an attempt has been made to improve the Mangat Strategy (1994) in view of the protection of privacy, variance and the range of .pi.. Conditions are obtained under which the proposed model is more efficient than those of warner (1965) and Mangat and Singh(1990).

• Communications for Statistical Applications and Methods
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• 제3권2호
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• pp.217-225
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• 1996

We propose a line process for edge detection which is easy to implement foe Bayesian image restoration. Comparisons are made between the proposed method and the method suggesed by Geman and Geman (1984) in two cases, simple image and complicated image. We show that the proposed method improve images mainly at the edges.

• Communications for Statistical Applications and Methods
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• 제7권1호
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• pp.37-46
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• 2000

We investigate some properties of commonly used residual plots in linear regression and provide some systematic insight into the relationships among the plots. We discuss three issues of linear regression in this stream of context. First of all we introduce two graphical comparison methods to display the variance inflation factor. Secondly we show that the role of a suppressor variable in linear regression can be checked graphiclly. Finally we show that several other types of standardized regression coefficients besides the ordinary one can be obtained in residual plots and the correlation coefficients of one of these residual plots can be used in ranking the relative importance of variables.