• Journal of the Korean Statistical Society
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• v.27 no.4
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• pp.435-449
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• 1998

In this paper, we consider the problem of constructing the lower cofidence intervals for the reliability P(X < Y z,w), where the stress X and the strength Y are the random variables with explanatory variables z and w, respectively. As an estimator of the reliability, a Mann-Whitney type statistic is considered. It is shown that under regularity conditions, the proposed estimator is asymptotically normal. Based on the result, the distribution free lower confidence intervals are constructed.

• The Pure and Applied Mathematics
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• v.20 no.2
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• pp.109-116
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• 2013

In this paper, we propose a Jonckheere type test statistic for testing the parallelism of k regression lines against ordered alternatives. The order restriction problems could arise in various settings such as location, scale, and regression problems. But most of theory about the statistical inferences under order restrictions has been developed to deal with location parameters. The proposed test is an application of Jonckheere's procedure to regression problem. Asymptotic normality and asymptotic distribution-free properties of the test statistic are obtained under some regularity conditions.

• Journal of Korean Medicine Rehabilitation
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• v.20 no.4
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• pp.105-130
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• 2010

Objectives : The purpose of this study was to assess the statistical methods errors used in the journal of Oriental Rehabilitation Medicine(JORM) and to identify the types of errors in statistical analysis. Methods : We reviewed quantitative articles that were published in the JORM from January 2005 through October 2009. Those were not used by statistical analysis such as literature studies, case study, review articles were not included in this analysis. A total of 296 articles was reviewed. We evaluated the adequacy and the validity of the statistical techniques with our checklist established be modified Lee's checklist, and three statistical evaluators assessed together to minimize bias. Results : Of the 222 articles, 213 were used in inferential and descriptive statistics. Of those 80% of articles adopting descriptive and inferential statistics were detected having statistical errors. One articles used 1.7 statistical method unit generally. Most frequently employed statistics were student t-test, one way ANOVA. pearson correlation analysis, Mann-whitney U test, paired t-test, and chi-square test in their order. However, most frequent statistics having errors were similar in order. The most common statistic errors were as follow: 1. absence of normality test, 2. misuse between paired test and unpaired test, 3. wrong choice of repeated measures analysis without consideration of time variables, 4, increase of Type I error by using inappropriate multiple test, 5. inappropriate application of discrete or categorical data instead of continuous data in correlation analysis, 6. poor consideration of basic consumption in chi-square test, 7. confusion between frequency comparison and average comparison, 8. mentioning the statistical technique without using it. Conclusions : We found various mistake or misuses in the applications of statistical methodologies in the articles published in the JORM. Careful consideration of statistical use and review from the specialist of statistics are warranted for improving the quality of JORM.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.6
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• pp.970-975
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• 2012

In Sasang constitutional medicine, doctors diagnose and treat patients according to their Sasang consitutition (SC) type. In this work, by a clinical test with a radial pulse tonometer, we investigated radial pulse properties which were significant in distinguishing unhealthy subjects from healthy subjects for each SC type. We measured radial pulse properties on left and right Gwan locations with a pulse tonometer for 299 elderly female subjects of age of 50 years old or above. We used a newly developed SCAT system to determine subjects' SC types. Subjects' health levels of either healthy or unhealthy were determined independently by two Korean medical doctors. To investigate the statistical differences, we used either of Student's t-test or Mann-Whitney U test depending on the normality of distribution of test statistic. For TE type, unhealthy subjects were characterized with significant increases in heart rate, systolic to diastolic period, pulse depth, while they showed significant decreases in width of pulse in normal direction, pulse area in diastolic period, and high harmonic components (6th, 7th) of power spectral density. For SE type, unhealthy subjects were characterized with significant increases in pulse pressure and pulse depth, while no significant differences were found for SY type. We investigated the characteristic differences in radial pulse properties due to change in health levels on each SC type for elderly females. Pulse variables which were significantly different between healthy subjects and unhealthy subjects were found to vary between SC types. For TE type subjects, many variables were found significant at the left Gwan location, which is in support of the theory of hyperactive liver functioning for TE type. Irrespective of the constitution, the related changes in the pulse properties due to worsened health level were in support of elevated blood flow amount in compensation with weakened blood circulatory function.