• Communications for Statistical Applications and Methods
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• v.6 no.3
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• pp.659-666
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• 1999

In comparing two population means, the test statistic depends on the sample means and the variances, which are very sensitive to the extremely large or small values. This paper aims at examining the behavior of such observations using proper criterion which can measure the influence of them. We derive a computationally feasible statistic which can detect influential observations on the two-sample t-statistic.

• Journal of Environmental Science International
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• v.20 no.9
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• pp.1183-1190
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• 2011

This study was aimed to establish the evaluating protocol and standard assessment for genetically modified (GM) hot pepper and to find out a proper statistic method to analyze for equality of agricultural characters between GM and non-GM pepper lines. GM and non-GM hot pepper lines were cultivated in two GMO fields in the middle region of Korea and total of 52 agricultural characters were collected during the plant growing season for 4 years, 2007 to 2010. Levene's test was conducted to confirm the homogeneity of raw data before statistic analysis. Two-way ANOVA in the multivariate tests and t-test were conducted to analyze 52 agricultural characters in order to find out the equality between H15 and P2377. From the statistical analysis through two-way ANOVA, 16 out of 16 plant growth traits, 9 out of 18 green fruit traits and 7 out of 18 red fruit traits among 4 years and 9 out of 16 plant growth traits, 4 out of 18 green fruit traits and 3 out of 18 red fruit traits between H15 and P2377 have shown the statistic differences. With the same raw data of 52 agricultural characters, t-test was also conducted. Based on the result from t-test, only 1 out of 16 plant growth traits, 2 out of 18 green fruit traits and 1 out of 18 red fruit traits have shown the differences between H15 and P2377, so that it was concluded that there is no statistic difference between H15 and P2377 in terms of agricultural characters. Also, the t-test is a proper statistic method to analyze each trait between GM and its control lines in order to evaluate agricultural characters.

• Journal of the Korean Statistical Society
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• v.33 no.3
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• pp.313-321
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• 2004

We consider the problem of testing cell probabilities in sparse multinomial data. Aerts et al. (2000) presented T=${{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2$ as a test statistic with the local least square polynomial estimator ${{p}_{i}}^{*}$, and derived its asymptotic distribution. The local least square estimator may produce negative estimates for cell probabilities. The local maximum likelihood polynomial estimator ${{\hat{p}}_{i}}$, however, guarantees positive estimates for cell probabilities and has the same asymptotic performance as the local least square estimator (Baek and Park, 2003). When there are cell probabilities with relatively much different sizes, the same contribution of the difference between the estimator and the hypothetical probability at each cell in their test statistic would not be proper to measure the total goodness-of-fit. We consider a Pearson type of goodness-of-fit test statistic, $T_1={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ instead, and show it follows an asymptotic normal distribution. Also we investigate the asymptotic normality of $T_2={{\Sigma}_{i=1}}^{k}{[{p_i}^{*}-E{(p_{i}}^{*})]^2/p_{i}$ where the minimum expected cell frequency is very small.

• Communications for Statistical Applications and Methods
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• v.29 no.3
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• pp.393-396
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• 2022

• The Journal of Engineering Geology
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• v.25 no.3
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• pp.331-337
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• 2015

A new technique is presented to detect unstable slope behavior, based on Hotelling's T² analysis of pore pressure and water content obtained during flume tests using granitic and gneissic weathered soils. Three sets of pore pressure-water content values were simultaneously obtained during each test, and T² statistics at the 90.0% and 95.0% confidence levels were calculated based on the correlations between values. The results show that unsuccessful detection of some local failures of the flume slope depended on the sensor position. In the case of global slope failures, anomalous behavior was detected between several hundred and several thousand seconds before the event as T² statistics exceeded the confidence interval 90%. Hotelling's T² analysis provides a single control criterion because it enables correlations between diverse measured values within the same slope; the criterion also includes stepwise criteria for a forecasting and warning system based on confidence levels.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.3
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• pp.357-366
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• 2006

We introduce the notion of intuitionistic fuzzy (t, s)-congruences on a lattice and study some of its properties. Moreover, we obtain some properties of intuitionistic fuzzy congruences on the direct product of two lattices. Finally, we prove that the set of all intuitionistic fuzzy congruences on a lattice forms a distributive lattice.

• Journal of Pharmacopuncture
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• v.9 no.2
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• pp.141-154
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• 2006

Objective : The purpose of this study was to compare and analyze the effect of ILIT and ELIT according to sex, age, disease on Hypercholesterolemia. Methods : The 73 patients who were irradiated to the Intravascular Laser and the 57 patients who were irradiated to the Extravascular Laser from 1999 to 2005 in Sam-se oriental medicine hospital were the study group. They were irradiated two or three times a week and checked total cholesterol before and after ten times of irradiation. The checked total cholesterol point, 150-199 were normal, 200-239 were borderline, over 240 were abnormal. They were classified into male and female(43 persons, 87 persons), adult and 01d(62 persons, 68 persons), cardiovascular disease and the other diseases(70 persons, 60 persons). Results : 1. Male, adult, and the other diseases groups were more effective in cholesterol reduction and in convertible change of each group than female, old, and cardiovascular disease groups, but only the convertible change of each group had statistic significance. 2. In male, old, and cardiovascular disease, ELIT was more effective than ILIT in cholesterol reduction and convertible change of each group, but this result didn't have statistic significance. 3. In female, ELIT was more effective than ILIT in cholesterol change but this result didn't have statistic significance. ILIT was more effective than ELIT in convertible change of each group and this result had statistic significance. 4. In adult and the other diseases, ILIT was more effective in cholesterol reduction, but this result didn't have statistic significance. ILIT was more effective than ELIT in convertible change of each group too and this result had statistic significance. Conclusion: It was thought to be undesirable to decide which is more effective treatment, but to be more desirable to choose one of ILIT or ELIT according to sex, age, disease than to decide it indiscriminately.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.19 no.2
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• pp.202-211
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• 2006

Objectives : This study is designed to evaluate correlation between the data of D.I.T,I examination in Bell's palsy and the improving period. Methods : This study researched into the clinical statistics for 50 patients who are in Bell's palsy and they are treated with oriental medical care of Dongshin university during 18months from January 1, 2005 to June 1, 2006. The data which examinated by D.I.T.I, are the thermal difference of normal and abnormal site of acupuncture int Gl4 BL2 GB3 S3 S4 S6 TE17 in Bell's palsy. Result : There was statistic significance between thermal difference of normal, abnormal site and the improving period. The period was shorter in normal thermal pattern than hypothermal pattern, hyperthermal pattern. Conclusion : According to the result, there was a statistic significance that more thermal difference and more difficult to recover in Bell's palsy.

• The Korean Journal of Applied Statistics
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• v.32 no.3
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• pp.331-348
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• 2019

Understanding the tumor heterogeneity due to differences in the growth pattern of metastatic tumors and rate of change is important for understanding the sensitivity of tumor cells to drugs and finding appropriate therapies. It is often possible to test for differences in population means using t-test or ANOVA when the group of N samples is distinct. However, these statistical methods can not be used unless the groups are distinguished as the data covered in this paper. Statistical methods have been studied to test heterogeneity between samples. The minimum combination t-test method is one of them. In this paper, we propose a maximum combinatorial t-test method that takes into account combinations that bisect data at different ratios. Also we propose a method based on the idea that examining the heterogeneity of a sample is equivalent to testing whether the number of optimal clusters is one in the cluster analysis. We verified that the proposed methods, maximum combination t-test method and gap statistic, have better type-I error and power than the previously proposed method based on simulation study and obtained the results through real data analysis.

• Perspectives in Nursing Science
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• v.10 no.2
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• pp.97-110
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• 2013

Purpose: This study sought to identify how initiating breastfeeding soon after birth affected breastfeeding practice. Methods: The subjects were mothers and newborns in Seoul's S. University Hospital maternity unit who elected to breastfeed. They were divided into an experimental group, which practiced an "early latching-on program" (latching-on within 30 minutes after birth), and a control group, which did not. Both groups' daily frequencies of breastfeeding and supplementary-glucose or bottle feeding were recorded. Results: The correlation between socio-demographic and medical characteristics and the breastfeeding rate was examined; 3 variables showed statistical significance: neonatal health anomaly, Apgar score after 1 minute, and Apgar score after 5 minutes. The difference in breastfeeding rates between the two groups was clear: the experimental group's rate was 1.93, while the control group's was 3.76 (t-statistic difference: 14.865), with the experimental group's rate during hospitalization being twice that of the control group (73.3% and 32.6%, respectively). Multiple regression analysis assessing the influence of the latching-on program yielded a t-statistic of -4.735 and a p-value of .000, indicating statistical significance. Conclusion: An early latching-on program's positive effect on the breastfeeding practice of mother's of newborns was demonstrated. Therefore, an early latching-on program could be a practical and effective nursing intervention for after mothers give birth.