• The Korean Journal of Financial Management
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• v.26 no.4
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• pp.191-234
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• 2009

This study examined on the volatility feedback hypothesis through the use of threshold GARCH-in-Mean (GJR-GARCH-M) model developed by Glosten, Jaganathan, and Runkle (1993) in the stock markets of 14 emerging countries during the period of January, 1996 to May, 2009. On this study, I found successful evidences which can support the volatility feedback hypothesis through the following three estimation procedures. First, I found relatively strong positive relationship between the expected market risk premiums and their conditional standard deviations from the GARCH-M model in the basis of daily return on each representative stock market index, which is appropriate to investors' risk-averse preferences. Second, I can also identify the significant asymmetric time-varying volatility originated from the investors' differentiated reactions toward the unexpected market shocks by applying the GJR-GARCH-M model and further find the lasting positive risk aversion coefficient estimators. Third, I derived the negative signs of the regression coefficient of unpredicted volatility on the stock market return by re-applying the GJR-GARCH-M model after I controlled the positive effect of predicted volatility through including the conditional standard deviations from the previous GARCH-M model estimation as an independent explanatory variable in the re-applied new GJR-GARCH-M model. With these consecutive results, the volatility feedback effect was successfully tested to be effective also in the various emerging stock markets, although the leverage hypothesis turned out to be insufficient to be applied to another source of explaining the negative relationship between the unexpected volatility and the ex-post stock market return in the emerging countries in general.

• Industry Promotion Research
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• v.3 no.1
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• pp.13-31
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• 2018

The purpose of this study is to investigate the effect of organizational culture on organization and organizational performance, and it was targeting for 350 public officials (local governments, foundation under local governments, public corporation) who research work and consulting were implemented for. When it comes to the response to questionnaires, 313 copies out of 350 were verified on the research hypothesis of the research model by using statistical package programs of SPSS 20.0 and AMOS 20.0. Results of the research hypothesis on research model show that firstly, regarding the research hypothesis 1 that the organizational culture of public organization will have a positive (+) significant effect on learning organization, the organizational culture recognized by the organizational members of public organizations showed a positive influence on the learning organization. In other words, it showed that the organizational culture recognized by the organization members of public organizations is a major factor in building a learning organization. Secondly, regarding the research hypothesis 2, the result of the relationship between organizational culture and organizational performance, that the organizational culture recognized by the organizational members of the public sector showed a positive influence and it implies the importance of recognizing and transforming the organizational culture of public organizations to improve organizational performance of public organizations. Thirdly, regarding the research hypothesis 3, the organizational culture recognized by the organizational members of public organizations showed an influence on organizational performance and also showed apositive(+) influence on organizational performance through learning organization. As the organizational culture recognized by the organization members in the public sectoris influencing the organizational performance through the learning organization, various implementation plans are required to improve organizational culture, improving learning organization, and improving organizational performance in accordance with the characteristics of public organizations.

• International Commerce and Information Review
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• v.14 no.4
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• pp.253-273
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• 2012

The purpose of this study was to examine the impact of the uncertainty of competitive environments on the commitment of manufacturing firms with distribution firms, their trust and long-term orientation in Korea, the United States and Japan. This study is of great significance in that it attempted to make a comparative analysis of the uncertainty of competitive environments among the three nations by selecting subjects not only from Korea but from the United States and Japan. A survey was conducted on the selected manufacturing firms, and the data from 105 Korean firms, 103 American companies and 83 Japanese firms were gathered. A structural equation was utilized to analyze the collected data. The findings of the study were as follows: Hypothesis 1 was rejected in Korea and Japan and was accepted in the United States. Hypothesis 2 was accepted in Korea yet not in the United States and Japan. Hypothesis 3 was accepted in all the nations. Hypothesis 4 was rejected in Korea and the United States and was accepted in Japan. Hypothesis 5 was accepted in all the nations, and Hypothesis 6 was accepted in every nation as well. In the future, the commitment, trust and long-term orientation 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 competitive environments should equally be investigated by making a comparative analysis.

• Korean Journal of Social Welfare
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• v.61 no.1
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• pp.323-357
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• 2009

This study illuminates the mechanism of life course on labor status of old age complementing the limits of labor status hypothesis of old age and model of statues attainment and combining them. The main results from this analysis are summarized in four points. Firstly, older men mostly engaged in agriculture, forestry and fishing industry or low-class occupations. A very small portion held high level or professional occupations. Regular full-time employees or employers were only 4.4% while, about 70% of older employees were temporal employees or self-employed. This shows that the elderly affluence hypothesis which alleges that most older men maintain high level occupations, applies to only a few. The second finding is that wealth differentials are sizable: about 20% of older workers own less than 50 million won, while 9.3% possess more than 600 million won. Therefore, it is not safe to claim that most people have accumulated enough wealth for old age according to the elderly affluence hypothesis. This gap being mainly reflected by education level, suggests that the model of status attainment is appropriate as wealth accumulation hypothesis. Thirdly, educational level determined not only lifetime careers, but also labor status of old age. Fourthly, using path analysis, the last finding is that education had effect on labor status of old age through lifetime career and wealth. That is, old men who have low education level had unstable lifetime career and own less wealth. They work in low income job, low social occupations and unstable occupation type in old age. This shows that life inequality continues until old age. Therefore, the inequality of education opportunity, spread of part-time work and small scale self employees should be discouraged. Furthermore, related policy should be provided in order to prevent being caught in unstable work.

• Korean Journal of Legislative Studies
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• v.24 no.2
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• pp.67-99
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• 2018

This study analyzes the revision bills of the National Assembly Law in the 19th National Assembly in which the National Assembly Advancement Act was enacted, with the question "who are involved in the revision of the procedural rules, and what motivates them?" The cosponsor network analysis focusing on primary sponsors of the revision bills shows that the network was constructed by party affiliations. A small number of members with high degree centrality attempted to cooperate with each other at the cosponsoring stage, but the legislation did not pass through the related committee. In addition, this study tests the four competitive hypotheses (the committee hypothesis, the distributive politics hypothesis, the ideological distance hypothesis, and the partisan affiliation hypothesis) about the motivation to propose amendments by using the regression models which include newly measured variables. Only the committee hypothesis and the partisan affiliation hypothesis are empirically supported. This implies that partisan consideration is still significant in amending the National Assembly Law even after the National Assembly Advancement Act, and thus party leaders' willingness to seek bipartisan compromises is at the heart of problem-solving.

• International Area Studies Review
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• v.17 no.4
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• pp.89-106
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• 2013

In this paper, we analysed the absolute and conditional convergency hypothesis and the determinants of productivity in manufacturing industries from 2000 to 2009 with 16 provinces and metro-cities by using panel analysis. In terms of convergency hypothesis test, the results show that both of the convergency hypothesis, the absolute vs. conditional hypothesis, reject the null hypothesis(H0) implying the labor productivity of the 16 province and metro-cities converged to the steady state equilibrium. Also, the speed of the absolute and conditional convergency for the 16 province and metro-cities are average 4.4% and 0.73% respectively. In addition, the results of the determinants of the labor productivity in manufacturing industry show that human capital and manufacturing location coefficient affect to the value- added per capita significantly, but government expenditure per capita doesn't affect to the value- added per capita. As for the total factor productivity, government expenditure per capita and fixed capital per capita are important factors, but research and development doesn't. Hence the government has to revise the balanced regional development policy to develop regional manufacturing industries for the vulnerable regions. Also, it requires more study regarding income disparities and productivity.

• Journal of The Korean Association of Information Education
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• v.25 no.3
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• pp.459-469
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• 2021

In this paper, a case study of basic data science practice education for field teachers and pre-service teachers was studied. In this paper, for basic data science education, spreadsheet software was used as a data collection and analysis tool. After that, we trained on statistics for data processing, predictive hypothesis, and predictive model verification. In addition, an educational case for collecting and processing thousands of public big data and verifying the population prediction hypothesis and prediction model was proposed. A 34-hour, 17-week curriculum using a spreadsheet tool was presented with the contents of such basic education in data science. As a tool for data collection, processing, and analysis, unlike Python, spreadsheets do not have the burden of learning program- ming languages and data structures, and have the advantage of visually learning theories of processing and anal- ysis of qualitative and quantitative data. As a result of this educational case study, three predictive hypothesis test cases were presented and analyzed. First, quantitative public data were collected to verify the hypothesis of predicting the difference in the mean value for each group of the population. Second, by collecting qualitative public data, the hypothesis of predicting the association within the qualitative data of the population was verified. Third, by collecting quantitative public data, the regression prediction model was verified according to the hypothesis of correlation prediction within the quantitative data of the population. And through the satisfaction analysis of pre-service and field teachers, the effectiveness of this education case in data science education was analyzed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.2
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• pp.82-101
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• 2023

This study is to identify the maintenance service quality of eco-friendly cars, which are rapidly increasing recently. Research is conducted by synthesizing research from the perspectives of internal employees and external customers by using the service profit chain model. Specifically, it is to study the overall structural relationship between internal customer satisfaction, physical quality, interaction quality, outcome quality, external customer satisfaction and long-term orientation. For the study, 202 questionnaires were collected from internal employees and 204 questionnaires from external customers. The results of testing the research hypotheses targeting the internal employee group are as follows. As a result of testing hypothesis 1, internal customer satisfaction has a significant positive (+) effect on physical quality and interaction quality. As a result of testing hypothesis 2, the service quality of eco-friendly car maintenance has a significant positive (+) effect on each other. As a result of testing hypothesis 3, physical quality and outcome quality have a significant positive (+) effect on external customer satisfaction. The results of testing the research hypotheses targeting an external customer group are as follows. As a result of testing hypothesis 2, in the relationship between eco-friendly car maintenance service quality, physical quality has a significant positive (+) effect on interaction quality, and interaction quality has a significant positive (+) effect on outcome quality. As a result of testing hypothesis 3, interaction quality and outcome quality have a significant positive (+) effect on external customer satisfaction. As a result of testing Hypothesis 4, external customer satisfaction has a significant positive (+) effect only on intention to reuse. Finally, as a result of examining the difference in perception between the internal employee group and the external customer group in eco-friendly car maintenance service quality and external customer satisfaction, it was verified that there was a significant difference only in outcome quality and external customer satisfaction.

• The Pure and Applied Mathematics
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• v.19 no.4
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• pp.363-381
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• 2012

Shortfall risk is considered by taking some exposed risks because the superhedging price is too expensive to be used in practice. Minimizing shortfall risk can be reduced to the problem of finding a randomized test ${\psi}$ in the static problem. The optimization problem can be solved via the classical Neyman-Pearson theory, and can be also explained in terms of hypothesis testing. We introduce the classical Neyman-Pearson lemma expressed in terms of mathematics and see how it is applied to shortfall risk in finance.

• Communications for Statistical Applications and Methods
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• v.21 no.1
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• pp.11-22
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• 2014

In this study, we propose a simultaneous test procedure based on the individual - values for each sub-null hypothesis with several well-known combining functions. We then compare the efficiency of our procedure with existing tests by obtaining empirical powers through a simulation study. Finally, we discuss some interesting features related to simultaneous test and point out a misconduct for the simulation study published in the previous work.