• Journal of the Korean Data and Information Science Society
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• v.28 no.3
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• pp.669-684
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• 2017

Mediation models are widely used in many fields of research and have recently gained attention in epidemiology. The mediation proportion is a standard measure to evaluate what part of the total exposure effect on an outcome may be explained by a particular mediator and to examine how important that pathway is relative to the overall exposure effect. A common question is how large a sample size is needed to achieve high statistical power or, equivalently, what magnitude of effect can be detected. Current power and sample size calculations for mediation analysis are limited and additional research is needed. We therefore propose a computer-intensive power analysis using the mediation proportion. We conduct simulation studies to calculate statistical powers and sample sizes. And then, we illustrate our power analysis using an example from the Adult Health Study of atomic-bomb survivors and demonstrate that the method is relatively straightforward to understand and compute.

• Journal of Preventive Medicine and Public Health
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• v.56 no.4
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• pp.303-311
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• 2023

Traditional mediation analysis, which relies on linear regression models, has faced criticism due to its limited suitability for cases involving different types of variables and complex covariates, such as interactions. This can result in unclear definitions of direct and indirect effects. As an alternative, causal mediation analysis using the counterfactual framework has been introduced to provide clearer definitions of direct and indirect effects while allowing for more flexible modeling methods. However, the conceptual understanding of this approach based on the counterfactual framework remains challenging for applied researchers. To address this issue, the present article was written to highlight and illustrate the definitions of causal estimands, including controlled direct effect, natural direct effect, and natural indirect effect, based on the key concept of nested counterfactuals. Furthermore, we recommend using 2 R packages, 'medflex' and 'mediation', to perform causal mediation analysis and provide public health examples. The article also offers caveats and guidelines for accurate interpretation of the results.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.642-651
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• 2018

This study aimed to verify the effects of parental chid-rearing attitudes on adolescents' aggressiveness and the mediation effects of peer attachment. To this end, the 7th year data (2016) (4th grade to the first year of high school) of Korea Children & Youth Panel Survey (KCYPS) were used. The results of this study are as follows: First, the correlations between child-rearing attitudes, aggressiveness, and peer attachment variables were confirmed. Second, parental child-rearing attitudes significantly affected adolescents' aggressiveness. Third, peer attachment showed some mediation effects in terms of the effects of parental child-rearing attitudes on adolescents' aggressiveness. For the significance verification of the mediation effects, the Sobel test was carried out. The results of this study are meaningful as empirical foundation. Based on the study results, this study suggested the need of education programs for parents and peer attachment consolidation programs for adolescents in relation with social welfare mediation practice.

• Korean Journal of Childcare and Education
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• v.12 no.3
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• pp.137-157
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• 2016

This study examines the effects of teacher's emotional intelligence on teacher-child interaction through the sequential mediation effects of efficacy belief about play and professional recognition. Participants were 268 teachers working at kindergartens in Gyeonggi area. Data were analyzed by descriptive statistic, Pearson's product-moment correlation, and the structural equation model using the SPSS 21.0 and Mplus 6.12 program. The main findings of this study are as follows: First, in regards to the relationship between emotional intelligence and teacher-child interaction, a single mediation effect of efficacy belief about play is significant. But there is no significant mediation effect of the professional recognition. Second, in regards to the pathway from emotional intelligence to teacher-child interaction, the professional recognition precedent mediation model is statistically significant, but efficacy belief about the play precedent mediation model is not significant. Based on the results, a concluding discussion was made regarding methods toward enhancing interaction between teacher and child.

• Korean Journal of Child Studies
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• v.37 no.6
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• pp.133-144
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• 2016

Objective: The purpose of this study was to identify the mediation effect of value of children in the relationship between maternal parenting stress and ideal number of children and to verify whether perception of the adequacy of national public childcare facilities moderates this mediation relationship. Methods: For the analysis, the 6th year results (2013) from the Panel Study on Korean Children by the Korean Institute of Child Care and Education were used. The main subjects of the study were 1,611 mothers with children aged 60 - 66 months. Results: First, there was a partial mediation effect of mother's parenting stress influencing the ideal number of children through the value of children. Second, the enhancing effect of the perception of the adequacy of national public childcare facilities moderating the value of children and ideal number of children was verified. Third, perception of the adequacy of national public childcare facilities had enforcing effects moderating the value of children and ideal number of children and mediation effects moderating the influence of maternal parenting stress on ideal number of children through the value of children. Conclusion: Based on the results, it was confirmed that the expansion of national public childcare facilities is a factor strengthening the maternal intention of birth.

• The Journal of Industrial Distribution & Business
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• v.9 no.4
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• pp.27-35
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• 2018

Purpose - The purpose of this research is to verify mediation effects of finance stress within relation structure between income inequality recognized by the elderly and life satisfaction. Research design, data, and methodology - In order to achieve the purpose of this research, we investigated recognition of income inequality of the elderly, finance stress and life satisfaction by using examination data aimed at 541 elderly people whose age is over 65 living in Chungcheongbuk-do. We conducted reliability, correlation, regression analysis_(tolerance limit and variance inflation factor) by using SPSS ver. 18.0. Results - From the result of analysis, it was proved that there are mediation effects of finance stress within the relation between income inequality recognized by the elderly and satisfaction with life. Based on this result, we suggest practical and political proposals to increase life satisfaction of the elderly. Conclusions - The purpose of this research is to verify mediation effects of finance stress in the relationship between income inequality and life satisfaction recognized by the elderly. From the result of research, first, a direct effect was discovered that as income inequality becomes high, life satisfaction will be decreased. Second, partial mediation effect of finance stress was confirmed in the relationship between income inequality and life satisfaction.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.24 no.3
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• pp.219-229
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• 2017

Purpose: The aim of this study was to examine the relationship between handwashing knowledge and handwashing compliance in nursing students and to identify the moderation and mediation effects of self-efficacy and perceived behavioral control on the relationship. Methods: The participants were 172 nursing college students who completed the self-report measures. Data were analyzed using t-test, ANOVA, and Pearson correlation coefficient, Multiple regression analysis was used to test moderation and mediation effects. Results: The score for knowledge of handwashing was higher in participants who had completed fundamentals of nursing practicum (t=-6.54, p<.001) and the score for compliance with handwashing was higher in participants who had completed clinical practicum (t=-3.81, p<.001) or fundamentals of nursing practicum (t=-5.97, p<.001). Self-efficacy showed a significant moderation effect (z=2.21, p=.027) but not a mediation effect while perceived behavioral control had a significant mediation effect but not a moderation effect on the relationship between knowledge of handwashing and compliance. Conclusion: Findings indicate that clinical practicum and fundamentals of nursing practicum were helpful to nursing students in acquiring knowledge and in practicing proper handwashing technique. These findings suggest that continuing and repetitive education programs on handwashing need to be enhanced and strategies to strengthen self-efficacy and perceived behavioral control need to be included in education programs.

• Journal of the Korea Convergence Society
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• v.9 no.2
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• pp.331-340
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• 2018

The purpose of this study is to verify resilience's mediation effects in the effects of adolescents' experience of abuse damage on aggressiveness in the convergence era. Towards this end, this study used the 7th year data (2016) (4th grade to the first year of high school) of Korea Children & Youth Panel Survey (KCYPS). The findings of this study are as follows: First, the correlations between experience of abuse damage, aggressiveness, and resilience variables were confirmed using multicollinearity VIF values. Second, adolescent's abuse experiences significantly affected their aggressiveness. Third, the partial mediation effects of resilience were shown in the effects of adolescents' experience of abuse damage on their aggressiveness. For the verification of mediation effects' significance, the Sobel test was carried out. The findings of this study are meaningful, as this study provides empirical data. Based on the findings, this study proposed the need of resilience consolidation programs for adolescents in the practice of social welfare.

• Journal of Information Technology Services
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• v.15 no.4
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• pp.111-123
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• 2016

The purpose if this study was to find and investigate effective mediation factors influencing performance of servitization through servitization acceptance activities by means of empirical results. According to the previous researches, two main mediation factors which were related with servitization competencies such as ICT competency of servitization and competency of servitization process were distinguished from lots of competencies which are relying on servitization process. Using a 373 sample data investigated from CEOs, directors and managers of small and medium sized firms in Korea, the structured mediation model was proposed. The measurement for the each variable was accepted for this study when the respondents were revealed to understand the servitization concepts which explained especially company's business moving towards the service specific gravity from selling existing products. The measurement for the each variable reflected that respondents were participating in any sort of servitization type or had intension to be involved with any servitization categories. The mediation hypotheses were tested in the way of analytical measures with the result of strong reliability. According to analysis, two mediators showed positive mediation role and statistically adopted between servitization acceptance activities and servitization performance in the 99% significant level. We confirmed that ICT competency of servitization and competency of servitization process were in the role of positive mediation between servitization acceptance activities and performance of servitization. The total of indirect effects were 0.2546 to support each mediation hypotheses. Tested two mediators were not on the same level. The most affecting mediation element on servitization performance was appeared as competency of servitization process. With the result of this study, we expect that the small and medium sized companies might have servitization business strategies including proper service competencies and mediators through acceptance activities to obtain suitable performance. According to the analysis, Companies which consider product-servitization need to set strategies to reinforce above two competencies.

• Journal of Distribution Science
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• v.17 no.11
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• pp.35-45
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• 2019

Purpose: The purpose of this study is to suggest strategic implications about empirical analysis with mediation effects of corporate image in terms of that relations between logistics culture safety, safety compliance and logistics performance of logistics companies. Research design, data and methodology: The structure and method of this research is organized with, first establishing hypothesis and research model based on previous study related to safety culture, safety compliance, corporate image, logistics safety and logistics performance, which has been carried out survey questionnaire to those who got involved in logistics businesses. Results: It is well justified that safety culture and safety compliance have significantly influenced to logistics performance as well as corporate images that is also revealed to have positive impact to logistics performance. With results verifying into mediation effects of corporate image, it is found that corporate image has partial mediation effects between logistics safety culture and logistics performance, and corporate image has full mediation effects between logistics safety compliance and logistics performance. Conclusions: In conclusion, it is strongly asked to make an aggressive efforts to safety compliance with necessity for spread of safety culture in level of enterprise. Planning the strategy and its implementation is required to secure safety in logistics process because both logistics performance and corporate image has positive influences by logistics safety.