• Communications for Statistical Applications and Methods
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• v.27 no.4
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• pp.397-412
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• 2020

In this paper, a notion of data depth is used to propose nonparametric multivariate two sample tests for difference between scale parameters. Data depth can be used to measure the centrality or outlying-ness of the multivariate data point relative to data cloud. A difference in the scale parameters indicates the difference in the depth values of a multivariate data point. By observing this fact on a depth vs depth plot (DD-plot), we propose nonparametric multivariate two sample tests for scale parameters of multivariate distributions. The p-values of these proposed tests are obtained by using Fisher's permutation approach. The power performance of these proposed tests has been reported for few symmetric and skewed multivariate distributions with the existing tests. Illustration with real-life data is also provided.

• Communications for Statistical Applications and Methods
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• v.10 no.3
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• pp.749-764
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• 2003

In this paper we explain that normal theory likelihood-ratio tests(z, t, $x^2$. F) for mean(s) or variance(s) can be geometrically related to volume of difference of two joint pdf's. One is an estimated joint pdf under null parameter space $\omega$ and the other is an estimated joint pdf under full parameter space $\Omega$. For explanations, ‘distance between two distributions’ is defined. We study properties of it, and derive some results on the distance between two multivariate normal distributions.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.400-403
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• 2002

This paper presents a shearographic technique for measuring in-plane strains. During the measurement, the test object is illuminated alternately with two laser beams, symmetrically with respect to the viewing direction. Employing a phase shift technique, the phase distributions due to object deformation for each beam are obtained separately. The difference of the two phase distributions depicts the derivative of in-plane surface displacements. The technique is equivalent to a system of many strain gages.

• The Korean Journal of Applied Statistics
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• v.22 no.1
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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.

• Communications for Statistical Applications and Methods
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• v.6 no.1
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• pp.237-249
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• 1999

It has been issued that the irreconcilability of the classical test for a point null and standard Bayesian formulation for testing such a point null. The infimum of the posterior probability of the null hypothesis is used as measure of evidence against the null hypothesis in Bayesian approach; here the infimum is over the family of priors on the alternative hypotheses which includes all density that are a priori reasonable. For iid observations from a multivariate normal distribution in $\textit{p}$ dimensions with an unknown mean and a covariance matrix propotional to the Identity we consider the difference and the Wolfowitz distance of the distributions of the P-value and the lower bound of the posterior probability over the family of all normal priors. The Wolfowitz distance is interpreted as the average difference of the quantiles of the two distrbutions.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.159-162
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• 2000

Interfacial and microfailure properties of carbon fiber/epoxy matrix composites were evaluated using both tensile fragmentation and compressive Broutman tests with acoustic emission (AE). Amino-silane and maleic anhydride polymeric coupling agents were used via the dipping and electrodeposition (ED), respectively. Both coupling agents exhibited higher improvements in interfacial shear strength (IFSS) under tensile tests than compressive cases. However, ED treatment showed higher IFSS improvement than dipping case under both tensile and compressive test. The typical microfailure modes including fiber break, matrix cracking, and interlayer failure were observed during tensile test, whereas the diagonal slippage in fiber ends was observed during compressive test. For both the untreated and treated cases AE distributions were separated well under tensile testing. On the other hand, AE distributions were rather closer under compressive tests because of the difference in failure energies between tensile and compressive loading. Under both loading conditions, fiber breaks occurred around just before and after yielding point. Maximum AE voltage fur the waveform of carbon or basalt fiber breakage under tensile tests exhibited much larger than those under compressive tests.

• Journal of the Korean Society of Clothing and Textiles
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• v.28 no.5
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• pp.559-569
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• 2004

The present study attempts to identify the differences in consumer information source, shopping orientation, and store image in the purchase of cosmetics in adult women at the age of 20 or more according to the distributions channels: department stores, specialty stores, discount stores and direct mails. From October 3 to 13, a survey was conducted to 1,200 adult women who visited each channel and who would understand the purpose of this study and complete the questionnaire. 300 sheets were distributed to each of the channels under investigation, and a total of 1,116 questionaaires were used in the final analysis. Using the statistical package, SPSS WIN 10.0, factor analysis, ANOVA, and Duncan's post-hoc test were carried out. The result are as follows: 1. There was a difference in the demographical characteristics of the consumers according to the distribution channels for cosmetics. 2. There was a differen co in the shopping orientations of the consumers according to the distribution channels for cosmetics. 3. There was a difference in the information sources of the consumers according to the distribution channels for cosmetics. 4. There was a difference in the store images perceived by the consumers according to the distribution channels for cosmetics.

• Journal of the Korean Data and Information Science Society
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• v.16 no.4
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• pp.1095-1106
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• 2005

When X and Y have independent two parameter exponential distributions, we develop a Bayesian testing procedures for the equality of two location parameters. The reference prior in non-regular exponential model is derived. Under this reference prior, we propose a Bayesian test procedures for the equality of two location parameters using fractional Bayes factor and intrinsic Bayes factor. Simulation study and some real data examples are provided.

• Communications for Statistical Applications and Methods
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• v.21 no.6
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• pp.539-559
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• 2014

We derive the exact distribution of summation for random samples from uniform distribution and then compare the exact distribution with the approximated normal distribution obtained by the central limit theorem. To check the similarity between two distributions, we consider five existing normality tests based on the difference between the target normal distribution and empirical distribution: Anderson-Darling test, Kolmogorov-Smirnov test, Cramer-von Mises test, Shapiro-Wilk test and Shaprio-Francia test. For the purpose of comparison, those normality tests are applied to the simulated data. It can sometimes be difficult to derive an exact distribution. Thus, we try two different transformations to find out which transform is easier to get the exact distribution in terms of calculation complexity. We compare two transformations and comment on the advantages and disadvantages for each transformation.

• Fashion & Textile Research Journal
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• v.1 no.2
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• pp.127-136
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• 1999

The purpose of this research was to investigate the difference between perceptions of the nude body and of the clothed body as measured by body cathexis scale. Subjects were 274 college male and female between 20~30 yrs. Data were analyzed by using frequency, T test, cluster analysis, Duncan test by using Spss for window 8.0 PC program. Significant difference were found between mean scores of male and female on the nude body cathexis (NBC) and clothed body cathexis (CBC) Scales for hair texture, hair color, face, face color, shape of head, eye, lips, forehead, back, trunk, waist, bust, leg of shape, chest, hip. On the difference between male and female, significant differences were found between NBC and CBC scales for all body parts except hair texture, face color, ears, eyes, teech. Male had higher satisfaction than female in both body cathexis. The taller men, the higher body satisfaction with face shape, body shape, height in both body cathexis. Before appearence management, the bigger men, the higher body satisfaction with musle, waist, height, chest, body shape in both body cathexis. Male had higher satisfaction than female in both body cathexis. The taller women, the higher body satisfaction with neck, body shape, height in before appearence management. The bigger women, the higher body satisfaction with heights, weight distributions, waist, height in both.