• Communications for Statistical Applications and Methods
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• v.10 no.2
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• pp.399-422
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• 2003

In actual manufacturing industries, process capability analysis often entails characterizing or assessing processes or products based on more than one engineering specification or quality characteristic. Since these characteristics are related, it is a risky undertaking to represent variation of even a univariate characteristic by a single index. Therefore, the desirability of using vector-valued process capability index(PCI) arises quite naturally. In this paper, some vector-valued ${PCI}_p$ ${C}_p$=(${C}_{px}$, ${C}_{py}$),${C}_{pk}$=(${C}_{pkx}$, ${C}_{pky}$) and ${C}_{pm}$=(${C}_{pmx}$, ${C}_{pmy}$) considering univariate PCIs ${C}_p$,${C}_{pk}$ and ${C}_{pm}$ are studied. First, we propose some asymptotic confidence regions of our vector-valued PCIs with bootstrap. And we examine the performance of asymptotic confidence regions of our vector-valued PCIs ${C}_p$ and ${C}_{pk}$ under the assumption of bivariate normal distribution BN($\mu_{x}$, $\mu_{y}$, $\sigma_{x}^{2}$, $\sigma_{y}^{2}$, $\rho$) and bivariate chi-square distribution Bivariate $x^2$(5,5,$\rho$).

• Architectural research
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• v.8 no.2
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• pp.1-10
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• 2006

This research has acquired preliminary information about the existing conditions and understanding of members regarding time management for members in the architectural field. The goal of this research is to construct a basis for the time management education framework in architectural field in the future. This research mainly focuses on following questions based on limited objectives: Do groups of academics and professionals have understanding and knowledge of time management? Can the level of an individual's scheduling techniques be correlated to the patterns of knowledge and understanding of time management principles and practices? Can the time management practice status in individual's working environment be correlated to the patterns of knowledge and understanding of time management principles and practices? Can an individual's self-confidence level be correlated to the patterns of knowledge and understanding of time management principles and practices? Data have been collected through comprehensive questionnaires given to academics and professionals in United States. By means of statistical analysis, the hidden patterns, deficiencies and relationships in attitudes about time management have been revealed. The statistical analysis has produced conclusions that, among several subdivisions, self-discipline and planning have strong relationships and confidence, personal organization, control, and information gathering subdivisions have certain relationships with objectives of time management education in this research.

• The Korean Journal of Applied Statistics
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• v.19 no.2
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• pp.349-360
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• 2006

PROC MIXED in SAS can be utilized to make inferences on parameters in a mixed model by use of Restricted Maximum Likelihood Estimation Method or Maximum Likelihood Estimation Method which has more merits than ANOVA method. A regression model with unbalanced nested error structure that belongs to a mixed model is used to construct confidence intervals on variances among groups, within groups, and regression coefficients in the model. PROC MIXED is applied to three different sample sizes for simulation. As a result of the simulation study, PROC MIXED generates confidence intervals on parameters that maintain the stated confidence coefficient in a large sample size. However, it does not generate confidence intervals that maintain the stated confidence coefficient for variance components among groups and intercept in a small sample size.

• The Korean Journal of Applied Statistics
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• v.19 no.2
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• pp.217-230
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• 2006

e discuss proper confidence intervals for interval estimation of a low binomial proportion. A large sample surveys are practically executed to find rates of rare diseases, specified industrial disaster, and parasitic infection. Under the conditions of 0 < p ${\leq}$ 0.1 and large n, we compared 6 confidence intervals with mean coverage probability, root mean square error and mean expected widths to search a good one for interval estimation of population proportion p. As a result of comparisons, Mid-p confidence interval is best and AC, score and Jeffreys confidence intervals are next.

• The Korean Journal of Applied Statistics
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• v.20 no.2
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• pp.257-266
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• 2007

It is known that Agresti-Coull approach is an effective tool for the construction of confidence intervals for various problems related to binomial proportions. However, the Agrest-Coull approach often produces a conservative confidence interval. In this note, confidence intervals based on a Bayesian approach are proposed for a linear function of independent binomial proportions. It is shown that the Bayesian confidence interval slightly outperforms the confidence interval based on Agresti-Coull approach in average sense.

• The Research Journal of the Costume Culture
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• v.14 no.4
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• pp.596-608
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• 2006

The purpose of this study was to reveal the relationship between self confidence in fashion coordination and fashion information search of men. This study also examine the utility of services of fashion coordination in fashion store. A questionnaire was developed and data was collected from 248 male consumer in the age of $20{\sim}29$ living in Busan and it was analyzed by the statistical method of frequencies, factor analysis, analysis of variance and regression. The results of this study were as follows: First, information contents of fashion coordination include four dimension, such as fashion style information, knowledge about fashion item, way of putting-on for stylish appearance and beauty information. And degree of search fashion information was significant different among groups classified by consumer's level of self confidence in fashion coordination. Second, multiple regression analysis revealed that consumer's self confidence in fashion coordination could be predicted from the amount of search fashion information contents and information sources. In conclusion, fashion information search was important factor which influenced on self confidence in fashion coordination. and male consumers perceived fashion coordination services in fashion store will be useful information.

• The Research Journal of the Costume Culture
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• v.21 no.4
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• pp.562-575
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• 2013

The purpose of this study was to test the determinants of fashion savvy. As determinants, this study examined fear of negative evaluation by others and self esteem as subject-related variables and consumer confidence in fashion decisions as the product-related variable. It was hypothesized that fear of negative evaluation and self esteem influence fashion savvy both directly and indirectly through consumer confidence in fashion decisions. Data were gathered by surveying university students in Seoul metropolitan area, using convenience sampling, and 311 questionnaires were used in the statistical analysis. In analyzing data, factor analysis and path analysis were conducted. Tests of the hypothesized path show that one factor of fear of negative evaluation and self esteem influence fashion savvy directly and indirectly through consumer confidence in fashion decisions. More specifically, 'fear of negative impression and judgment' factor negatively influences 'marketing literacy' and 'consumer selfefficacy' of fashion savvy, whereas self-esteem positively influences 'consumer self-efficacy' of fashion savvy. In addition, consumer confidence in fashion decisions influences all six factors of fashion savvy. The implications of these findings and suggestions for future study are also discussed.

• The Korean Journal of Applied Statistics
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• v.16 no.2
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• pp.377-393
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• 2003

Several confidence interval estimates for the difference of two binomial proportions were introduced. Bootstrap confidence interval is also suggested. We examined the over estimation property of approximate intervals and under estimation trend of exact intervals for the difference of proportions. We compared these confidence intervals based on the average coverage probability, expected width and skewness measure. Particularly actual coverage probability were calculated by using the prior distribution of parameters. Monte Carlo simulation for small sample size is conducted. Some interesting contour plots of average coverage probability and marginal plots for several interval estimates are presented.

• 한국체육학회지인문사회과학편
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• v.55 no.5
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• pp.43-55
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• 2016

The purpose of this study is to verify analysis of self-efficacy and self-confidence of the athletes. The subjects of this study were selected 200 athletes who have a highschool athletes in Seoul. The data-collecting method use of self-confidence by Kim(1999) and self-efficacy by Kim(2002) & Lee(2003). The Descriptive Statistical Analysis Correlation Analysis and Regression Analysis As a result, Frist, family interest, motivation, mentor & hobby which is sport-state/trait affected confidence. Second, family interest, motivation, mentor & hobby which is affected self-efficacy. Third, sport-trait confidence which is affected self-efficacy.

• Communications for Statistical Applications and Methods
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• v.5 no.2
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• pp.491-501
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• 1998

Motivated by bioequivalence studies which involve comparisons of pharmaceutically equivalent dosage forms, we propose a more general decision rule for showing equivalence simultaneously between multiple means and a control mean. Namely, this testing procedure is concerned with the situation in that one must make decisions as to the bioequivalence of an original drug product and several generic formulations of that drug. This general test is developed by considering a spherical confidence region, which is a direct extension of the usual t-based confidence interval rule formally approved by the U.S. Food and Drug Administration. We characterize the test by the probability of rejection curves and assess its performance via Monte-Carlo simulation. Since the manufacturer's main concern is the proper choice of sample sizes, we provide optimal sample sizes from the Monte-Carlo simulation results. We also consider an application of the generalized equivalence test to a repeated measures design.