• 한국농공학회지
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• 제24권1호
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• pp.53-62
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• 1982

This study was attempted to find best fitted distribution and the equations for probable maximum flow with the evaluation of parameters by the method of moment for the rat- ional design of hydraulic structures in the annual exceedance series. Six subwatersheds were selected as studying basins along Geum River basin. The results obtained through this study were analyzed and summarized as follows. 1. Fitted probability distribution was showed in the order of Three Parameter Lognorm al, Type 1 Extremal, Exponential, Pearson Type III, and Log Pearson Type I distribu- tion as the results of x$^2$ goodness of fit test. 2. Kolmogorov-Smirnov test showed in the order of Three Parameter Lognormal, Exp- onential' Pearson Type III, Log Pearson Type III and Type 1 Extremal distribution for the fitted probability distribution. 3. It can be concluded that Three parameter Lognormal distribution is a best fitted one among some other distributions out of respect for each both tests. An Exponential distribution was proposed as a suitable one by Chow, V.T. showeci lower fittness than that of Three Parameter Lognormal in Geum River basin. 5. Probable flood flow equations followins the return periods for each station were obt- ained by Three Parameter Lognormal distribution. 6. It is urgently essential that best fitted probability distribution should be established for the annual exceedance series in the main river systems of Korea.

• 통합자연과학논문집
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• 제7권3호
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• pp.208-213
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• 2014

National-wide and/or large scale sample surveys generally use complex sample design. Traditional Pearson chi-square test is not appropriate for the categorical complex sample data. Rao-Scott suggested an adjustment method for Pearson chi-square test, which uses the average of eigenvalues of design matrix of cell probabilities. This study is to compare the efficiency of Rao-Scott first order adjusted test to Wald test for homogeneity between two populations using 2009 Gyeongnam regional education offices's customer satisfaction survey (2009 GREOCSS) data. The 2009 GREOCSS data were collected based on stratified three-stage cluster sampling with probability proportional to size. The empirical results show that the Rao-Scott adjusted test statistic using only the variances of cell probabilities is very close to the Wald test statistic, which uses the covariance matrix of cell probabilities, under the 2009 GREOCSS data based. However it is necessary to be cautious to use the Rao-Scott first order adjusted test statistic in the place of Wald test because its efficiency is decreasing as the relative variance of eigenvalues of the design matrix of cell probabilities is increasing, specially more when the number of degrees of freedom is small.

• 한국수학사학회지
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• 제26권4호
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• pp.277-299
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• 2013

It was not until the early twentieth century that statistics emerged as an independent academic discipline. The developments of statistical theory and methods would not have been possible without heated controversies among founding fathers. One of them, controversy on the statistical test between R. A. Fisher and J. Neyman, E. S. Pearson had been very fierce and long-lasting. On the other hand it was in the early twentieth century that psychologists began to utilize statistical test which was a hybrid of tests developed by Fisher and Neyman-Pearson. By considering the history of fields such as psychology, we can see distinctive characteristics specific to the history of statistics.

• 한국콘텐츠학회논문지
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• 제19권3호
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• pp.163-170
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• 2019

본 연구는 발달장애아동과 비장애아동 299명을 대상으로 K-CPQ의 신뢰도 및 타당도를 검증하여 국내 발달장애아동의 참여수준을 평가할 수 있는 도구임을 입증하고자 하였다. K-CPQ의 신뢰도를 검증하기 위해 Cronbach ${\alpha}$값을 구하고 검사-재검사 신뢰도검사를 위해 Pearson 적률상관관계 분석을 실시하였다. 그 결과 K-CPQ의 각 영역에서 내적일치도(${\alpha}=.81{\sim}.90$)는 비교적 높은 신뢰도를 보였고, 검사-재검사 신뢰도검사에서는 Pearson 상관계수(r= .807~.843)가 모든 영역에서 유의미한 상관관계를 보였다(p<.01). K-CPQ의 판별타당도의 검증을 위해 장애아동과 비장애아동 그룹의 각 영역을 비교한 결과 모든 영역에서 통계적으로 유의미한 차이(t=2.32~5.18)를 보였다(p<.05~p<.01). K-CPQ의 준거타당도 검증을 위해, K-SMS와 K-SFA의 Pearson 상관관계 분석을 한 결과 통계학적으로 유의한 정적 상관관계(r= .817, r=.743)를 보였다(p<.01). 본 연구를 통해, K-CPQ가 신뢰도 및 타당도를 갖춘 평가도구임을 확인하였으며, 앞으로 K-CPQ의 다각적인 연구로 장애아동의 사회참여와 통합을 위해 적절한 중재를 제공하기 위한 평가도구로 유용하게 사용되기를 기대한다.

• Archives of Plastic Surgery
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• 제38권3호
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• pp.245-250
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• 2011

Purpose: Composite tissue allotransplantation has emerged as a new therapeutic modality to reconstruct major tissue defects of the head, neck and extremities. A questionnaire-based instrument, the Louisville Instrument for Transplantation (LIFT), has been developed to objectively assess the risk-versus-benefit ratio for composite tissue allotransplantation procedures. The objective of this study is to assess if the LIFT is a useful, reliable and valid tool to apply to the Korean population. Methods: Seventy-three medical students and 60 lay public completed the LIFT questionnaire (translated to Korean) over the period from February 2010 to April 2010. Internal consistency was assessed using Cronbach's alpha. Test-retest reliability was analyzed using Pearson's correlation coefficient. Construct validity was assessed by comparing Pearson's correlation coefficients between perceived improvements in quality of life and responses to risk tolerance questions concerning organ transplants. Results: Measurements of the test-retest reliability showed that Pearson's correlation coefficients ranged from 0.241 to 0.902, and Cronbach's alphas ranged from 0.52 to 0.80 for medical students and from 0.63 to 0.83 for the lay public. Pearson's correlation coefficients showed significant correlations between perceived improvements in quality of life and responses to risk tolerance questions concerning organ transplants. Hand transplant showed a significant correlation in medical students. Foot, hand, two hands, larynx, partial face transplants showed significant correlations for the lay public. Conclusion: The applicability of the LIFT to the Korean population was found to be reliable and valid. The LIFT may serve as a useful tool for clinical application in the Korean population.

• 대한안전경영과학회지
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• 제10권2호
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• pp.205-210
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• 2008

The research interprets the principles of sampling error design for quality statistics models such as hypothesis test, interval estimation, control charts and acceptance sampling. Introducing the proper discussions of the design of significance level according to the use of hypothesis test, then it presents two methods to interpret significance by Neyman-Pearson and Fisher. Second point of the study proposes the design of confidence level for interval estimation by Bayesian confidence set, frequentist confidential set and fiducial interval. Third, the content also indicates the design of type I error and type II error considering both productivity and customer claim for control chart. Finally, the study reflects the design of producer's risk with operating charistictics curve, screening and switch rules for the purpose of purchasing and subcontraction.

• Communications for Statistical Applications and Methods
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• 제23권5호
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• pp.433-444
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• 2016

When we observe binary responses in a cluster (such as rat lab-subjects), they are usually correlated to each other. In clustered binomial counts, the independence assumption is violated and we encounter an extra-variation. In the presence of extra-variation, the ordinary statistical analyses of binomial data are inappropriate to apply. In testing the homogeneity of proportions between several treatment groups, the classical Pearson chi-squared test has a severe flaw in the control of Type I error rates. We focus on modifying the chi-squared statistic by incorporating variance inflation factors. We suggest a method to adjust data in terms of dispersion estimate based on a quasi-likelihood model. We explain the testing procedure via an illustrative example as well as compare the performance of a modified chi-squared test with competitive statistics through a Monte Carlo study.

• Communications for Statistical Applications and Methods
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• 제16권4호
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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.

• International Journal of Oral Biology
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• 제46권4호
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• pp.168-175
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• 2021

To investigate the perceptions and attitudes of dental hygienists toward radiation safety management in Korea. A total of 800 dental hygienists were randomly selected for an anonymous survey, and 203 of them participated. The questionnaire items included the following: sex, career period, type of installed radiographic equipment, recognition of the diagnostic reference level (DRL), participation in radiation safety education, and attitudes toward radiation protection for both patients and dental hygienists. The participants were divided into two groups according to their years of experience (< 10 years versus ≥ 10 years). The difference between the groups was investigated according to frequency distribution. Fisher's exact test or Pearson's chi-square (𝛘²) test was used as appropriate. A regression analysis was performed to investigate the impact of wearing a thyroid collar for personnel protection during patient radiation exposure. The types of installed radiographic equipment included panoramic radiography (96.1%), cephalometric radiography (76.9%), intraoral radiography (72.9%), and cone-beam computed tomography (69.5%). Significant differences were observed in the learning pathway for the DRL (Fisher's exact test, p < 0.05), satisfaction with radiation safety education (Pearson's 𝛘² test = 5.3975, Pr = 0.02), and use of personnel radiation monitoring systems (Pearson's 𝛘² test = 18.1233, Pr = 0.000) between the groups. Significant differences were also observed in personnel protection using a thyroid collar and patient protection during panoramic radiography (odds ratio = 14.2). Dental hygienists with more than 10 years of experience were more satisfied with radiation safety education and more interested in radiation monitoring. Considering career experience, customized, continuous, and effective radiation safety management education should be provided.

• 대한물리치료과학회지
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• 제6권4호
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• pp.221-227
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• 1999

This study is about the correlation of pain strength between Oswestry Disability Index and Hendler 10-Minute Screening Test in the patient of low back pain. The subject were 66, in and out patient who had recieved physical therapy on low back pain in several hospitals at Seoul and Kyungkido. during July 5.-August 27. 1999 1. The average score of Oswestry Disability Index was $24.06{\pm}8.16$ and that of Hendler 10-Minute Screening Test was $24.82{\pm}4.31$. 2. The Pearson's R score between each questionnaires of Oswestry Disability Index and pain strength was .5692. p<0.0001. So it is very high. But, that between each questionnaires of Hendler 10-Minute Screening Test and pain strength was not significant.. 2261 p<0.05 3. The Pearson's R score between Pain strength of Oswestry and person care was .3391, sex life was .3756, social life was .4637 (p<0.005) and that between Pain factor of Hendler, pain area of Hendler and sleeping(4358), sex(.6198), position change(2767), (p<0.005). So it is significant. 4. The categories where we could see the correlation between Pain strenth of Oswestry and Hendler each questionnaires were sleeping(.3222), sex(5524), position change(4291). (p<0.005).