• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.12
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• pp.999-1006
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• 2014

Mindlin plate theory includes the shear deformation and rotatory inertia effects which cannot be negligible as exciting frequency increases. The statistical methods such as energy flow analysis(EFA) and statistical energy analysis(SEA) are very useful for estimation of structure-borne sound of various built-up structures. For the reliable vibrational analysis of built-up structures at high frequencies, the energy transfer relationship between out-of-plane waves and in-plane waves exist in Mindlin plates coupled at arbitrary angles must be derived. In this paper, the new wave transmission analysis is successfully performed for various energy analyses of Mindlin plates coupled at arbitrary angles.

• Journal of Elementary Mathematics Education in Korea
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• v.24 no.1
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• pp.1-30
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• 2020

This study was carried out in order to identify the error types of statistical graphs for statistical literacy education. We analyze the meaning of using graphs in statistical problem solving, and identify categories, frequencies, and contexts as the components of statistical graphs. Error types of representing categories and frequencies make statistics consumers see incorrect distributions of data by subjective point of view of statistics producers and visual illusion. Error types of providing contexts hinder the interpretation of statistical information by concealing or twisting the contexts of data. Moreover, the findings show that tasks provide standardized frame already for drawing graphs in order to avoid errors and pay attention to the process of drawing the graph rather than statistical literacy for analyzing data. We suggest some implications about statistical literacy education, ethical problems, and knowledge for teaching to be considered when teaching the statistical graph in elementary mathematics classes.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.411-420
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• 2006

There are many statistical information sites as the use of internet is increased quickly in recent years. In this paper, we explore and analyze internet sites for statistical information such as statistical survey system, education, database, and terminology. And then we classify these sites to apply statistical information to some particular spheres easily. Also, we analyze the patent map for domestic patents of statistical information. In so doing, the result of this study aims at enhancing our understanding of internet sites for statistical information.

• Journal of Chest Surgery
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• v.27 no.9
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• pp.732-737
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• 1994

From January 1983 to December 1992, There were 1441 papers in the Korean Journal of Thoracic and Cardiovascular Surgery. Among these papers, 783[54.3%] were original article or clinical analysis and 652[45.2%] were case reports. A total of 319 papers contained some statistical analysis. In 150 cases[47.0%] of these 319 papers, the statistical description was insufficient. Of the correctly described papers, 115[68%] had more than one statistical error. Of course, in many cases the errors were not considered to be severe, but they were often sufficient to raise doubts about some inferences. We suggest that authors should be more careful when they describe and apply statistical methods. If possible, authors should interpret results with statistical specialists. And we also suggest that our society have more extensive statistical refereeing system. This would at least prevent the worst errors from appearing in print. The last suggestion is elementary instruction in statistical methods during preclinical training.

• Communications for Statistical Applications and Methods
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• v.16 no.3
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• pp.437-447
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• 2009

Recently, in addition to analyzing data with appropriate statistical methods, statistical analysts in the industrial fields face difficulties that they have to compose proper datasets for analysis objectives via extracting or generating processes from diverse data storage devices. In this paper we survey and compare many state-of-the-art data access technologies adopted by several commonly used statistical packages. More understanding of these technologies will help to reduce the costs occurring when analyzing large size of datasets in especially data mining works, and so to allow more time in applying statistical analysis methods.

• Education of Primary School Mathematics
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• v.12 no.2
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• pp.133-143
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• 2009

In this thesis, we conduct a comprehensive analysis of the current situation and the inherent problems found in modern statistics education in Elementary School. There are statistical curriculum, 7th textbook of elementary school level, practise of statistics class, connection of real life etc. Through analysis of these given problem, we explore the future direction of statistical education. Therefore, the statistical learning to make statistical situations and pose problems based on students' interests and students-related situations should be an effects on positive mathematical attitude and statistical thinking which could develop understanding statistical problems and thinking.

• Communications for Statistical Applications and Methods
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• v.28 no.2
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• pp.135-150
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• 2021

We propose principal differential analysis based classification methods. Computations of squared multiple correlation function (RSQ) and principal differential analysis (PDA) scores are reviewed; in addition, we combine principal differential analysis results with the logistic regression for binary classification. In the numerical study, we compare the principal differential analysis based classification methods with functional principal component analysis based classification. Various scenarios are considered in a simulation study, and principal differential analysis based classification methods classify the functional data well. Gene expression data is considered for real data analysis. We observe that the PDA score based method also performs well.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.581-585
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• 2010

This study introduced a Bayesian based frequency analysis in which the statistical trend seasonal analysis for hydrologic extreme series is incorporated. The proposed model employed Gumbel and GEV extreme distribution to characterize extreme events and a fully coupled bayesian frequency model was finally utilized to estimate design rainfalls in Seoul. Posterior distributions of the model parameters in both trend and seasonal analysis were updated through Markov Chain Monte Carlo Simulation mainly utilizing Gibbs sampler. This study proposed a way to make use of nonstationary frequency model for dynamic risk analysis, and showed an increase of hydrologic risk with time varying probability density functions. In addition, full annual cycle of the design rainfall through seasonal model could be applied to annual control such as dam operation, flood control, irrigation water management, and so on. The proposed study showed advantage in assessing statistical significance of parameters associated with trend analysis through statistical inference utilizing derived posterior distributions.

• Journal of Korean Academy of Nursing
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• v.45 no.5
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• pp.641-649
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• 2015

Purpose: The purpose of this study was to introduce the main concepts of statistical testing and effect size and to provide researchers in nursing science with guidance on how to calculate the effect size for the statistical analysis methods mainly used in nursing. Methods: For t-test, analysis of variance, correlation analysis, regression analysis which are used frequently in nursing research, the generally accepted definitions of the effect size were explained. Results: Some formulae for calculating the effect size are described with several examples in nursing research. Furthermore, the authors present the required minimum sample size for each example utilizing G*Power 3 software that is the most widely used program for calculating sample size. Conclusion: It is noted that statistical significance testing and effect size measurement serve different purposes, and the reliance on only one side may be misleading. Some practical guidelines are recommended for combining statistical significance testing and effect size measure in order to make more balanced decisions in quantitative analyses.

• The Korean Journal of Applied Statistics
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• v.32 no.1
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• pp.15-27
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• 2019

The reliability of the data means the overall consistency of the measurement results. Methods for evaluating reliability have been continuously studied because it affects the results of the statistical analysis. Cronbach's ${\alpha}$ coefficient or intraclass correlation coefficient is used for reliability evaluation; however, these measures cannot be applied to data consisting of three-dimensional coordinates to represent an object. In this study, we propose a measure to evaluate the reliability of three dimensional shapes based on statistical shape analysis that is made possible by extracting the shape information from the measured three dimensional coordinates and decomposing the shape variation.