• The Korean Journal of Applied Statistics
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• v.14 no.1
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• pp.103-110
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• 2001

This paper considers a multistage experiment. Response scales can be same or different from stage to stage. When variables are of nested structure, the response variable at each stage can be defined conditionally. For analysing such data with compound scales, this paper suggests a sequnce of dependence models and shows how to set up a sequence of models for the driver's liscense test data.

• The Korean Journal of Applied Statistics
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• v.35 no.6
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• pp.703-724
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• 2022

Although longitudinal studies mainly produce multivariate longitudinal data, most of existing statistical models analyze univariate longitudinal data and there is a limitation to explain complex correlations properly. Therefore, this paper describes various methods of modeling the covariance matrix to explain the complex correlations. Among them, modified Cholesky decomposition, modified Cholesky block decomposition, and hypersphere decomposition are reviewed. In this paper, we review these methods and analyze Korean children and youth panel (KCYP) data are analyzed using the Bayesian method. The KCYP data are multivariate longitudinal data that have response variables: School adaptation, academic achievement, and dependence on mobile phones. Assuming that the correlation structure and the innovation standard deviation structure are different, several models are compared. For the most suitable model, all explanatory variables are significant for school adaptation, and academic achievement and only household income appears as insignificant variables when cell phone dependence is a response variable.

• International Commerce and Information Review
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• v.16 no.1
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• pp.163-183
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• 2014

This paper empirically investigated whether the strategic performance of dependence and commitment on output sector uncertainty based on the data from manufacturing firms in Korea. U.S. Also, the proposed model was proven by the structural equation model with the data gathered from 105 manufacturing firms in Korea, 103 in U.S. The success of the members of channel having limited resources and capabilities depends on how they cope with environment. Especially, it is insispensable for manufacturing firms and distributing firms to build up win win systems when environmental uncertainty is high in the output sector. The findings were as follows. Hypothesis 1 was accepted in all the nations. Hypothesis 2 was accepted in the United States yet not in Korea. Hypothesis 3, 4 was accepted in Korea yet not in the United States. Hypothesis 5 was accepted in every nation as well. In the future, the dependence, commitment and strategic performance of manufacturing and distribution firms should be investigated from a mutual perspective, and additional data should be obtained by selecting more subjects. As for environmental uncertainty, the uncertainty of distribution environments as well as output sector uncertainty should equally be investigated by making a comparative analysis.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.185-189
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• 2006

Time series analysis is a frequently effective method of constructing model and prediction in data processing of deformation monitoring. The monitoring data sample must to be as more as possible and time intervals are equal roughly so as to construct time series model accurately and achieve reliable prediction. But in the project practice of GPS deformation monitoring, the monitoring data sample can't be obtained too much and time intervals are not equal because of being restricted by all kinds of factors, and it contains many variates in the deformation model moreover. It is very important to study the data processing method for small samples and multi-variates time series in GPS deformation monitoring. A new method of establishing small samples and multi-variates deformation model and prediction model are put forward so as to resolve contradiction of small samples and multi-variates encountered in constructing deformation model and improve formerly data processing method of deformation monitoring. Based on the system theory, a deformation body is regarded as a whole organism; a time-dependence linear system model and a time-dependence bilinear system model are established. The dynamic parameters estimation is derived by means of prediction fit and least information distribution criteria. The final example demonstrates the validity and practice of this method.

• Korean Journal of Health Education and Promotion
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• v.21 no.1
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• pp.137-151
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• 2004

Objectives： This study aims to investigate the psychological factors associated with abstention following a smoking cessation program, and to suggest useful information for those who want to stop . smoking and health practitioners who help them Methods： Participants were 73 smokers (65 males, 8 females) that participated in a hospitalized smoking cessation program, whose mean age was 44.89 (SD＝9.61). Participants completed questionnaires and psychological tests including： Demographic sheet, Eysenck's Personality Questionnaire, Multidimensional Coping Scale, Fagerstrom Test for Nicotine Dependence, and Jerusalem and Schwarzer's Self-Efficacy Scale. To identify whether the subjects abstained or not and to encourage them to abstain, the researcher called them on the telephone once a week for three months. After three months, they were contacted every other week till six months passed since they had left the smoking cessation program Tthey were THEN contacted once a month for another six months. The data was analyzed by using ANCOVAs with SPSS 10.0 for Windows. Results： 42 (57.5％) out of 73 abstained for one month and 26 (35.6％) abstained for one year. People who failed to abstain within a month showed a higher psychoticism and introversion personality trait than those who abstained for one month, while people who abstained for one month were coping actively in most situations, showed a higher self-efficacy and lower nicotine dependence than those who failed to abstain within a month, and people who failed to abstain within a year showed a higher psychoticism than those who abstained for one year. While people who abstained for one year were coping actively, obstinate, and interpreting positively most situations, they showed a higher self-efficacy than those who failed to abstain within a year. Conclusion： These findings reiterate the roles of personality, self-esteem, nicotine dependence in smoking and suggest the roles for smoking cessation. And it was found the roles of coping styles ,in smoking cessation. It might help smokers who want to stop smoking and health practitioners who help them

• Korean Journal of Social Welfare
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• v.63 no.4
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• pp.83-107
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• 2011

This study examines the duration dependence in the exit rate from National Basic Livelihood Protection Program(NBLP). If the length of time on welfare is negatively correlated with the exit rate after controlling for 'unobserved heterogeneity', the observed declining exit rates would provide evidence of true duration dependence. Data are drawn from Korean Welfare Panel study 2005~2008. A variety of discrete-time hazard models are estimated, including parametric/nonparametric hazard model, gamma frailty hazard model/mass point technique model. It is found that welfare dynamics in Korea does not show strong evidence of duration dependence after controlling for unobserved heterogeneity. All the models estimated show that this finding is quite robust. The observed declining exit rate is largely due to differences in the unobservable characteristics of recipients. Thus, the detrimental effect of the welfare on the preference and attitude among recipients is not likely to be strengthened as time on welfare increases.

• Journal of Korean Medical Ki-Gong Academy
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• v.13 no.1
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• pp.105-144
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• 2013

This study intended to provide fundamental data to take countermeasures against recurrent stress by analyzing the health-related quality of life and factors for recurrent stress of alcohol dependents. Structured questionnaire was prepared for patients who quitted drinking after they had been hospitalized for alcohol dependence to take medical treatment but suffered recurrence, and analysis on health-related quality of life and environmental factors with drinking risk was conducted. The quality of life was at a relatively satisfactory level, where pain was found at the highest level and general health condition was found at the lowest level. Environmental factors with drinking risk were found to be a moderate level, drinking for the reason of family and friends in terms of complications with other persons was found to be highest, and then job, self control, bad emotions, and social pressure on drinking were found in order. For health-related quality of life, the quality of life was found to be high in case of the only son, professional job, well-educated persons, and no history of hospitalization. Regarding factors for recurrent stress, stress was found to be high in case of the eldest son and being without religion, and the lower was the quality of life, the higher were recurrent stress and environmental factors with drinking risk. It was found that demographic factors including age, marriage, and job influenced the recurrence of alcohol dependence, and factors for recurrent stress, etc. also influenced recurrent alcohol dependence with drinking risks. Specially, the lower was the quality of life, the higher were factors for recurrent stress, and drinking risks, therefore measures to improve the quality of life are required to be taken to prevent alcohol dependence from recurrence.

• Journal of Korean Academy of Nursing
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• v.37 no.7
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• pp.1139-1148
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• 2007

Purpose: The purpose of this study was to investigate the effects of a community-based group smoking cessation program among adult smokers in a rural community. Method: The study design was quasi-experimental with a pre and posttest. A total of 55 adult smokers participated in the study. They were evaluated 1, 3, and 6 months after the program to identify the long-term effectiveness of the program. The program consisted of a total of 5 sessions provided twice a week. To test the effectiveness of the program, urine creatinine, expired air carbon monoxide, nicotine dependence, and smoking-related knowledge were used as dependent variables. Data was analyzed with the SPSS 10.0 program with a t-test, paired t-test, and Scheffe test. Result: Urine creatinine, expired air carbon monoxide, and nicotine dependence were significantly decreased after the program. Also, the rates of continuous abstinence were 81.8% at posttest, 65.5% at 1 month, 54.5% at 3 months, and 54.5% at 6 months follow-up. Conclusion: This community-based group smoking cessation program implemented by a nurse and smoking cessation counselors was effective for quitting smoking and decreasing urine creatinine and nicotine dependence. Therefore, this smoking cessation program could be recommended to induce smoking cessation as health promotion management in the rural community.

• The Korean Journal of Applied Statistics
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• v.27 no.2
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• pp.291-305
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• 2014

Persistence is one of the typical characteristics appearing in the volatility of financial time series. According to the recent researches, the volatility persistence may be due to either volatility shifts or long-range dependence. In this paper, we consider residual-based CUSUM tests to distinguish volatility persistence, long-range dependence and volatility shifts in GARCH models. It is observed that this test procedure achieve reasonable powers without a size distortion. Moreover, we employ AIC and BIC criteria to estimate the change points and the number of change points in volatility. We demonstrate the superiority of residual-based CUSUM tests on various Monte Carlo simulations and empirical data analysis.

• Journal of Family Relations
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• v.22 no.2
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• pp.71-97
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• 2017

Objectives: The purpose of this research was to analyze the influence of self-actualization needs, dependence on parents, and work-family balance stress affecting on the marriage friendly attitudes among the unmarried women in twenties and thirties. Method: The participants were 315 unmarried women connected by SNS. The data were collected by questionnaire method through SNS by the smart phone using by the snowball sampling method and analyzed by t-test, ANOVA, and hierarchical multiple regression analysis. Results: First, there were significant differences in the marriage friendly attitudes according to education level, religion, dating. In the case of college graduates, having religion and dating partner, unmarried women had more marriage friendly attitudes. Second, the results of multiple regression showed that the marriage friendly attitudes among unmarried women was significantly influenced by education, religion, and the humanity factor among the self-actualization needs, emotional dependence on parents and work-family balance stress. In addition, the humanity factor among the self-actualization needs was found to be the most influential factor on the marriage friendly attitudes among unmarried women in this study. Conclusion: This study suggests the importance of emphasizing humanity education, having the emotional close relationship with the parents, and enforcing social systems for work-family balance for the greater marriage friendly attitudes of unmarried women in twenties and thirties.