• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.3
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• pp.216-222
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• 2002

Autocorrelation in time series data can affect statistical inference in correlation or regression analyses. To improve a regression model from which the residuals are autocorrelated, Yule-Walker method, nonlinear least squares estimation, maximum likelihood method and 'prewhitening' method have been used to estimate the parameters in a regression equation. This study reviewed on the estimation methods of preventing spurious correlation in the presence of autocorrelation and applied the former three methods, Yule-Walker, nonlinear least squares and maximum likelihood method, to a 20-year real data set. Monte carlo simulation was used to compare the three parameter estimation methods. However, the simulation results showed that the mean squared error distributions from the three methods simulated do not differ significantly.

• The Journal of the Convergence on Culture Technology
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• v.6 no.2
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• pp.25-31
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• 2020

We aimed to investigate the moderating effect of kindergarten teachers' resilience in the relation between job stress and psychological burnout. The subjects were 164 early childhood teachers in Metropolitan area, South Korea. We measured subjects' job stress, psychological burnout, and resilience using the questionnaires. The collected data were analyzed with descriptive statistics, Pearson correlation analyses, and the analyses of hierarchical regression using SPSS 21.0. As results, kindergarten teachers' job stress showed the significantly positive correlation with their psychological burnout, but resilience showed the significantly negative correlation with it. It was found that kindergarten teachers' resilience had the moderating effect in the relation between job stress and psychological burnout.

• Korean Journal of Childcare and Education
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• v.19 no.5
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• pp.1-20
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• 2023

Objective: The purpose of the present study was to examine the associations between affective commitment, social support, and life satisfaction among child care teachers. Methods: One hundred fifty-four child care teachers in the metropolitan area of Seoul completed a questionnaire on affective commitment, social support, and life satisfaction. Descriptive statistics, correlation analyses, hierarchical multiple regression analyses using the bootstrapping method were conducted. Results: The results showed that affective commitment predicted increased life satisfaction. The results also revealed significant moderation effects of social support on the relationship between affective commitment and life satisfaction. Further analyses revealed significant moderation effects of support from directors and colleagues on the relationship. Conclusion/Implications: The findings highlight the importance of affective commitment in enhancing life satisfaction among child care teachers. The positive association is more pronounced among child care teachers who perceive social support, highlighting the supportive roles of directors and colleagues in enhancing life satisfaction among child care teachers.

• Water for future
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• v.29 no.4
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• pp.119-129
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• 1996

The daily soil water contents were obtained from the time domain reflectometry (TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comparison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at small watersheed scale. The degree of similarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with eddy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at small watershed scale have no significant difference.

• Journal of the Korean Data and Information Science Society
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• v.23 no.3
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• pp.457-465
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• 2012

The purpose of this study is to analyze the association between indicators and to find statistical models based on important indicators at 'College Notifier' in Korea Council for University Education. First, Pearson correlation coefficients are used to find statistically significant correlations. By variable selection method, the important indicators are selected and their coefficients are estimated. As variable selection method, backward and stepwise methods are employed.

• Korean Journal of Exercise Nutrition
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• v.14 no.2
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• pp.81-86
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• 2010

The purpose of this study was to identify the factors associated with child's Body Mass Index (BMI) and physical activity. The participants (n = 133) were Korean juveniles (3^rd and 4^th graders) and their parents. They completed a questionnaire packet including the SPARK (Sports, Play, and Active Recreation for Kids) survey and the parent equivalent survey. Correlation, multiple linear regression and binary logistic regression analyses were applied to identify the association between child's BMI and 10 factors of SPARK as predict or variables. 25.6% of the participants were classified as overweight (21.1%) or obesity (4.5%). 3 parental factors including mother's BMI and frequency of mother's and father's physical activity were identified as significant predictors of children's BMI. The 10 variables accounted for 28% of the variance (p<.01) in the linear regression model. These results provide insight into parental factors which are related to a child's BMI and physical activity. Parental role modeling which refers to parents' efforts to model an active lifestyle for children plays an important role.

• Anatomy and Cell Biology
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• v.51 no.4
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• pp.251-259
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• 2018

The aim of this study is to examine the correlation between tooth wear and age by quantitatively measuring maxillary first molar wear in children. A total of 150 maxillary dental models were analyzed in 30 subjects (male, 11; female, 19) with an age range of 6-14 years. Maxillary first molar wear were assessed based on area, volume and the shortest distance from the buccal occlusal plane to the central pit point (BCPH). The area and volume of the tooth cusps were measured at four different offset-plane heights (0.2, 0.4, 0.6, and 0.8 mm). Relationship between age and the amount of wear or BCPH were statistically analyzed. Correlation and regression analyses were also performed, and age estimation was obtained with linear regression analysis. Repeated measures analysis of variance (ANOVA) revealed significant differences between age and the amount of wear based on area, volume, and offset-plane height. Except age of 8 and 10, 12 and 14's 0.2-mm offset-plane-measured volume, all area and volume measurement of all ages and offset-plane height showed a significant amount of increase. Wear speeds were calculated using the BCPH. Among age and measurement variables, the correlation coefficient was strongest when the volume was measured from the 0.4-mm offset-plane. As age increases, the amount of wear, as quantified by area and volume measurements, also increases. According to this study, a regression equation that can be used for age estimation is follows: Age $(y)=0.16{\times}0.4V+0.85$ ($R^2=0.490$) using volume.

• Korean Journal of Human Ecology
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• v.21 no.2
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• pp.257-267
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• 2012

The purpose of this study was to observe work-related emotional consequences in call center employees. The data were collected from 434 employees in 3 call centers by way of a self-administered questionnaire. Frequencies, Cronbach's alpha, T-test, one-way ANOVA, Pearson's correlation analysis, and multiple regression analyses were conducted by SPSS Win 18.0. The results of this study were as follows: first, job burnout proved to be significant, and demonstrated a positively correlation to surface acting and negatively correlation to deep acting. Second, altruism proved to be significant and demonstrated a positive correlation to deep acting, while also demonstrating a negatively correlation to both sex and surface acting. Third, conscientiousness proved to be significant and demonstrated a positive correlation to both age and deep acting, as well as a negatively correlation to surface acting. Finally, work-family conflict proved to be significant and demonstrated a positive correlation to both sex and workload in terms of hours per day.

• Journal of the Korean Society of Clothing and Textiles
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• v.36 no.1
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• pp.36-45
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• 2012

This study locates factors that affect the intention to use fashion SNS (social network service) and intention for word-of-mouth on fashion SNS. Independent variables were fashion shopping orientation, attitude toward innovative products, fashion leadership, and demographics. A questionnaire method was used to collect data on college students while factor analyses, multiple regression, $x^2$ analyses, and Pearson correlation coefficients were applied in analyzing data. Factor analyses resulted in four factors for fashion shopping orientation, three on attitude toward innovative products and two on fashion leadership. Multiple regression analyses showed that information compatibility of attitude toward innovative products had a significant impact on two models of intention to use fashion SNS and two models of intention for word-of-mouth on fashion SNS. Opinion leadership and gender were significant factors for two models of intention to use fashion SNS, which means that women are likely to have more intention to use fashion SNS. Meanwhile, fashion innovativeness was found to be a significant factor on two models of intention for word-of-mouth on fashion SNS. Shopping orientation factors were not important for any model. $x^2$ analyses showed that women rather than men wanted more information on online fashion shows, general fashion information, and user participation programs. Fashion major students wanted more information on online fashion shows and user participation programs than non-fashion major students.

• The Korean Journal of Applied Statistics
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• v.25 no.5
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• pp.865-875
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• 2012

In this study, we identify the variables that affect the number of crime and spatial correlation in the Seoul metropolitan area, in addition, we measure the relative risk on the incidence of crime by a Poisson regression model. We suggest a statistical methodology to make a risk map for crime based on relative risk instead of the total event of crime by region using the Geographic Information System. To demonstrate the use and advantages of this methodology, this study presents an analyses of the total crime count in 25 wards in the Seoul metropolitan area.