• Communications for Statistical Applications and Methods
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• v.17 no.6
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• pp.899-907
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• 2010

Several non-response imputation methods are suggested, however, mainly cross-sectional imputations are studied and applied to this analysis. A simple and common imputation method for panel data is the cross-wave regression imputation or carry-over imputation as a special case of cross-wave regression imputation. This study suggests a multiple imputation method combined time series analysis and cross-sectional multiple imputation method. We compare this method and the cross-wave regression imputation method using MSE, MAE, and Bias. The 2008 monthly labor survey data is used for this study.

• Journal of Navigation and Port Research
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• v.44 no.5
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• pp.400-406
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• 2020

In this study, we first measured the malmquist productivity index by DEA among the Korean public firms. Second, there are 12 public corporations whose productivity (MPI) has decreased compared to 2014. This is mainly because of a decrease in productivity, as well as a decrease in the technical efficiency change index (TECI), impacted by the internal environment, and the increase in productivity because of an increase in the technology change index (TCI) impacted by the external environment. Finally, the analysis of the impact on the management assessment scores showed that the productivity (MPI), scale efficiency (CRS), size of sales, operating profitability, and total capital investment efficiency are significantly related (+), except for the asset turnover, which is a static financial ratio. Meanwhile, the management evaluation scores between the high-productivity public corporations and low-performing public corporations were significantly discriminating. Thus, it is confirmed that the nation's state-run companies must manage their MPIs in a time series to score high in management evaluation.

• Korean Journal of Social Welfare Studies
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• v.47 no.4
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• pp.309-332
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• 2016

This research attempts to calculate the vertical equity of National Health Insurance Contribution of locally provided policy holders by abilities to pay. Also, this longitudinal study examined the influence of abilities to pay and demographic characteristics on the health insurance premium. Using data from the Korea Welfare Panel Study, this study followed the self-employed households who continued to participate in the survey from 2011 to 2015. Kakwani's index of progressivity was measured as a measure of vertical equity and panel regression analysis was conducted by STATA program. The results of this research are as follows. First, from 2011 to 2015, the values of kakwani's index were negative according to composite income, which meant some levels of regressiveness of contribution. Secondly, panel regression analysis showed that the lowest household of composite income had a significantly negative effect on premiums, which also meant regressiveness. Based on the results, the author suggested political discussions on reorganizing the system of imposing the National Health Insurance contribution.

• Environmental and Resource Economics Review
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• v.33 no.1
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• pp.59-86
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• 2024

Recently, research on city gas demand is increasing by reflecting the characteristics of each region. The similarity of the social structure of the adjacent region and the density of the supply infrastructure induce spatial correlation with the clustering that has a microscopic relationship between regions. Accordingly, as a result of analyzing the spatial correlation after dividing the demand for city gas for civilian use into a total of 54 regions based on the jurisdiction of 34 city gas companies, it was confirmed that there was a positive spatial correlation from a global and local perspective. In this study, the demand for city gas for civilian use for 54 regions from January 2014 to December 2022 was composed of panel data, and the spatial panel regression analysis and the general panel regression analysis were compared, and it was found that the spatial error model (SEM) was the most suitable model. This presents policy and practical implications by confirming that the demand for city gas for civilian use in one region has a significant relationship with the adjacent region.

• Journal of Digital Convergence
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• v.14 no.2
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• pp.197-208
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• 2016

In this paper, data mining regression analysis and decision tree analysis techniques were used to analyze factors affecting the life satisfaction of middle school students. For this purpose, we analyzed Korean Children and Youth Panel Survey(KCYPS) data. As results, the common influencing factors to the life satisfaction were derived from regression analysis. Those factors are self-esteem, depression, total grade satisfaction, regional community awareness, career identity, annual delinquency damage experience, siblings' factors, trust, behavioral control, and concentration. Based on the result described by decision tree analysis, the factors that indicate a significant impact on the life satisfaction of middle school students were self-esteem, depression, career identity and attention factor.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.487-488
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• 2006

In these days, demand of a LCD monitor is remarkably increasing with development of the LCD technology. However, there are thermal problems for improvement of efficiency for the LCD monitor. Thus, this research analyzed thermal problems such as convection and conduction heat transfer characteristics in the LCD monitor using an infrared (IR) camera. Also, the results of the outer side of the front LCD panel using the IR camera have been compared with the results of the inner side of the front panel using T-type thermocouples. The equations have been derived for the temperature distribution of the inner side of the front LCD panel by a multiple regression method including variables for ambient temperature, humidity and temperature differences between the front and back panels of the LCD monitor.

• Journal of Digital Convergence
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• v.17 no.4
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• pp.65-73
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• 2019

This study performed Panel Regression Analysis (PRA) with the debt ratio as a dependent variable and the ROE (return on equity), sales volume, current ratio, total capital, and Shanghai Containerized Freight Index (SCFI) as an independent variable. According to the GLS analysis, the current ratio to liabilities ratio was negative, and for sales, the ratio of liabilities was positive. Capital totals also had a negative impact on the debt ratio. However, ROE, unlike the hypothesis, had negative effects on the liability ratio, and the SCFI index was not significant. As implications of this research, the company confirmed that its sales increased as the debt ratio of global shipping companies rose, achieving economies of scale. However, it was confirmed that the actual size of the economy through the injection of other capital would help increase sales but not affect net profit. Shipping companies should expand their business power and secure large container vessels to secure credibility of shippers. In the future research, an analysis considering exchange rate, global economic growth rate, and manufacturing production index is needed.

• International Commerce and Information Review
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• v.12 no.4
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• pp.151-170
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• 2010

The present study made an empirical analysis for investigating the competitiveness of technology trades in Korea. In particular, the study deduced the correlation between technology export and technology import using the variables of Gross Domestic Expenditure on R&D and Per capita industry value added Productivity and employed fixed effect model in panel linear regression model. It is found that the R&D expenditure of OECD countries made a significant effect on the technology import and the value-added labor productivity made a significant result on both technology export and import. Therefore, it showed that the technology trade in Korea made a sensitive response to labor productivity in OECD countries. By panel analysis, machine, construction, ICT, and service industry affect most on technology export in Korea for recent 5 years. For technology import, electric-electron, chemical, service, and construction industry have significant effects. This study contributed to understanding of industrial characteristics affecting technology trades in Korea and empirical analysis to show correlation between the factors affecting technology trade.

• Journal of the Korean Data and Information Science Society
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• v.25 no.4
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• pp.715-725
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• 2014

This study uses a quantile regression analysis to investigate intergenerational economic mobility in Korea. The analysis is based on data from the 1st through 11th waves of the Korean Labor and Income Panel Study (KLIPS) conducted from 1998-2008. The household nature of the data allows us to link parents' incomes to children's incomes at different points in time. Using a quantile regression analysis instead of mean one reveals that the effect of fathers' earnings are different across the conditional distribution of sons' earnings, particularly being larger on the upper quantile than on the lower quantile. After controlling effect of sons' college education by including a dummy variable for the degree, however, the pattern among quantile effects for fathers' earnings is no longer clear. Instead a new pattern emerges that education has a much larger effect on the upper quantiles than on the lower ones. Using nonparametric estimates of conditional density curves based on the quantile regression results, we derive some interesting features in graphical forms, which are not obvious in numerical analysis.

• The Journal of Industrial Distribution & Business
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• v.9 no.8
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• pp.17-26
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• 2018

Purpose - Indonesian economy often receives negative impact from external factors, particularly through trade linkage. To mitigate that impact, the export market and product diversification should be established. Latin America is one of the potential regions to augment the Indonesian export market. Research design, data, and methodology - This study attempts to classify the potential market and product for Indonesian export, particularly in Latin America, by using panel regression, trade complementarity, and export similarity index over the period 2000-2015. Regression was also used to examine whether the presence of the Indonesian Trade Promotion Center (ITPC) can support diversification. Results - Based on regression results, those indexes established Chile, Uruguay, Suriname, and Ecuador as the priority countries with the products: animal and vegetable oils, fats and waxes; chemicals and related products; miscellaneous manufactured articles; commodities and transactions. Conclusions - The results of the regression concludes that the trade complementarity index gave a significant positive effect to boost Indonesian export, whereas, the export similarity index gave a significant negative effect. The regression also conclude that ITPC gave a significant positive impact on Indonesian export. For instance, the government should prioritize those countries and products and also develop ITPC there to optimize Indonesian export.