• The Korean Journal of Applied Statistics
• /
• v.34 no.5
• /
• pp.697-710
• /
• 2021

Relative error prediction is preferred over ordinary prediction methods when relative/percentile errors are regarded as important, especially in econometrics, software engineering and government official statistics. The relative error prediction techniques have been developed in linear/nonlinear regression, nonparametric regression using kernel regression smoother, and stationary time series models. However, random effect models have not been used in relative error prediction. The purpose of this article is to extend relative error prediction to some of generalized linear mixed model (GLMM) with panel data, which is the random effect models based on gamma, lognormal, or inverse gaussian distribution. For better understanding, the real auto insurance data is used to predict the claim size, and the best predictor and the best relative error predictor are comparatively illustrated.

• Environmental and Resource Economics Review
• /
• v.27 no.1
• /
• pp.195-214
• /
• 2018

This study estimates the price elasticity of residential water demand in Korea. For that, annual panel data from the year of 2010 to 2013 for 161 local water services is estimated by using panel quantile model. As a result, the price elasticities of residental water demand in Korea are estimated to be between -0.156 and -0.189 depending on its quantile. In addition, the study finds that the estimated elasticity of residential water demand by traditional conditional mean regression is relatively more influenced by high demand areas because the distribution of residental water demand in Korea is left-skewed.

• Survey Research
• /
• v.9 no.2
• /
• pp.51-83
• /
• 2008

While online surveys are considered to be the viable alternative to face-to-face and telephone surveys, many clients express a strong concern about the possibility of unreliable responses. Given this concern, survey experts hypothesize that amounts of time on responding can represent the extent to which respondents fill out the questions with sincerity. This study examines this hypothesis using data from an online survey sample of 1.052. Results strongly suggest that while "long time" informants are reliable, "short time" informants are not. Those in the short time group spend only 2.4 seconds per question and show very different patterns of responses to 49 Likert -typed questions. Logistic regression results imply that these unreliable respondents are interested in monetary gifts and maybe as a result, participate in surveys much more frequently. In conclusion, we provide some implications of these results to the quality of online surveys.

• Journal of the Economic Geographical Society of Korea
• /
• v.17 no.1
• /
• pp.129-146
• /
• 2014

This paper investigates how industrial diversity affects unemployment and employment instability from the perspective of the regional economy. Through this analysis, we examine how the industry-specific policy to promote some industry strategically in most of areas affects the stability of the regional economy. We measure Herfindahl indexes using the 1993-2010 data of 16 regions in Korea, and use panel regression model for empirical analysis. The main results from this empirical analysis are summarized as follows. First, we confirm that the industrial structure of most regions has been changed to the direction of specialization in 1990s and to the direction of diversification in 2000s through analyzing the changes in the values of Herfindahl indexes during the given period. Second, we find from the estimation results of panel regression model that the higher industrial diversity in most of regions is, the lower the unemployment rate is. However, a statistically significant relationship between industrial diversity and employment instability only partially confirmed. Third, there exist high unemployment rate and employment instability in most metropolitan areas, but it is hard to say that this relationship is highly statistically significant. From the results of the empirical analysis, it is likely that the industry-specific policies such as the regional strategic industry development policies unlike policy goals make the unemployment rate to rise and economic instability to increase. From the viewpoint of employment aspects, the strategies to increase industrial diversity would be desirable rather than those to specialize in the industrial structure.

• Journal of Industrial Convergence
• /
• v.22 no.2
• /
• pp.1-12
• /
• 2024

This study investigates what decisions have an impact on bank performance. A panel regression analysis was conducted using data from the financial statements of banks located in the United States from 2013 to 2022, and the effects of explanatory variables were examined through hierarchical panel regression analysis divided into financial decision-making and management decision-making. In addition, by analyzing performance separately from the creditor and shareholder perspectives (hereinafter referred to as overall) and from the shareholder perspective alone, it suggests which elements should be utilized and how to improve performance from each perspective. When a panel regression analysis was performed using only liquidity and stability, dependency on deposits and the interest coverage ratio had a statistically significant impact from the perspective of overall performance, and the debt ratio also had a statistically significant impact from the perspective of shareholder performance. When adding non-technical factors, only the labor cost ratio among non-technical factors was found to be statistically significant from the overall performance perspective, and although the non-technical factors were not statistically significant from the shareholder performance perspective, the cash ratio was found to have a statistically significant impact. Lastly, when adding technical innovation elements, the intangible asset ratio was not statistically significant from the overall performance perspective, but was significant from the shareholder performance perspective. The significance and implications of this study are that there are differences in factors that can affect the performance of overall or shareholder and that various decision-making factors can affect a bank's performance.

• Journal of the Korea Convergence Society
• /
• v.6 no.4
• /
• pp.121-126
• /
• 2015

Korea Youth Panel (2008) has 2 panels of the 5th year of Knowledge data to perform statistical analysis and regression analysis, the risk factors in the risk conditions of the family of functional deficits, protective factors, the relationship between the mediating effect of psychological adaptation and protective factors verification mechanisms and the psychological adaptation level it is an objective to analyze the protective factors that protect the high youth. To investigate the differences by frequency analysis and personal characteristics of the analyte's was performed t test using PASW (Predictive Analytics Software) 18.0. And to verify the effect of the parameters is performed rank regression analysis for verification of the effects of protection factors for adaptation. Rather than focusing on youth risk factors in social welfare practice field, focusing on processes and protective factors to reduce the risk factors, it is possible to convert the viewpoint overlooking the youth exposed to risk factors. Also, for young people experiencing difficulties that features loss of the family, it is determined that the prepared foundation which can be provided in the direction of social welfare practical intervention.

• Health Policy and Management
• /
• v.34 no.1
• /
• pp.87-93
• /
• 2024

Background: In recent years, studies have shown conflicting results regarding the benefits of dietary supplements in reducing healthcare expenditures. This study aimed to address this inconsistency by examining the association between supplement consumption and health expenditures using nationally representative data from the Korea Health Panel Survey (2019-2020). Methods: A 1:1 matched case-control dataset was established using propensity score matching technique based on supplement consumption. Then, total annual healthcare expenditures were compared between the two groups. In addition, a multivariate regression analysis (Proc Surveyreg) was performed to determine the association between the supplement consumption and medical costs. Results: The supplement user group spent about 1.72 million Korean won, while the non-user group spent about 1.43 million Korean won on medical services (p=0.0186). The results of multivariate regression showed that the costs were approximately 26.15% higher in the user group than in the non-user group (p=0.0004). Conclusion: Contrary to the previous studies that have shown the benefits of supplement use in reducing healthcare costs, this study showed that those who consistently consumed supplements spent more on medical services. This can be interpreted in the same context as previous studies suggesting that dietary supplement intake is a healthy behavior for managing one's health. However, we caution against drawing firm conclusions due to data limitations. Further analysis using patient-level epidemiologic data is needed.

• Journal of the Korea Convergence Society
• /
• v.10 no.7
• /
• pp.391-397
• /
• 2019

In 2016, the number of suicides per 100,000 population in Korea was 24.6, which is the highest record of OECD countries. The number of suicide deaths increased with age. Elderly people have a higher risk of completed suicide than any other age group. The purpose of this study was to analyze the panel data of the Korean Welfare Panel Study to identify the factors affecting the suicide of Korean older people. This study analyzed the data of the 11th Korean Welfare Panel Study, which was constructed in 2016. The mean age of the participants was 75.55 years and 37% were man and 63% were women. The annual prevalence of suicidal ideation was 3.4%. The effects of depression(Exp(B)=1.113) and subjective health status((Exp(B)=.767) on suicidal ideation was statistically significant by stepwise logistic regression analysis(Nagelkerke $R^2=.248$). Therefore, for the effective application of suicide prevention program for the older people, assessment of subjective health status and depression screening should be preceded.

• The Journal of the Korea Contents Association
• /
• v.17 no.11
• /
• pp.135-142
• /
• 2017

The importance of trade cooperation with foreign countries is becoming higher in order to utilize the competitiveness of its own country's industries. In Korea, the government has made various efforts to respond to the expansion of foreign trade cooperation. As time goes by, it is needed to redefine and reestablish the functions of industrial polices in order to improve the effectiveness and efficiency of foreign trade cooperation. We focus on the industrial and trade policies related to FTA. Mainly we do research the impact (before and after FTA) of industry, trade policies, and firms' management activities on the export-oriented firms. For this end we conduct a survey on the firms' evaluation of the trade related policies and analyze with the panel data regression model. According to the results, in order to enhance the utilization of FTA, the connection with export support program, the training of expert HRs, and the prohibition of double regulation are the main influential policies.

• Journal of the Korean Data and Information Science Society
• /
• v.26 no.2
• /
• pp.429-440
• /
• 2015

This study was to investigate factors influencing the school adjustment according to gender and body mass index (BMI) of middle school students who participated in the 2nd-wave Korea Children and Youth Panel Study (KCYPS). This study used a crosssectional design with secondary analysis with KCYPS. The variables were parental interest, behavioral problem, aggression, attention problem, somatic symptom, social withdrawal, depression, and academic achievement. The data were analyzed with descriptive statistics, Pearson's correlation coefficients, and multiple regressions. School adjustment was significantly associated with academic achievement high, explaining 11.3~19.1% of the variance in boys. School adjustment was significantly associated with attention problem, explaining 14.9~42.4% of the variance in girls. Factors influencing school adjustment were significantly different according to gender and BMI. To improve the school adjustment, it is necessary to develop gender-specific school adjustment promotion programs according to BMI.