• International Journal of Highway Engineering
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• v.16 no.5
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• pp.143-154
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• 2014

PURPOSES : This study drew factors affecting motorcycle accidents in Seoul by severity using an ordered probit model and aimed to analyze and verify the drawn influence factors. METHODS : As the severity of the accidents could be classified into three types (fatal injury, serious injury and minor injury), this study drew the factors affecting accidents by a comparative analysis employing an ordered probit model, removed the variables that would not secure significance sequentially to construct a model with high explanatory power regarding the factors affecting the severity of motorcycle accidents, and calculated the marginal effect of each factor to understand the degree of each factor's impact on the severity. First, Model 1 put in all variables; Model 2 was constructed by removing the variables of the road surface conditions that could not meet the level of significance (p=0.608); Model 3 was constructed by removing gender variable (p=0.423); and Model 4 was constructed finally by removing age variable (p=0.320). RESULTS : As a result of an analysis, statistically significant variables were time of occurrence, type of accident, road alignment and motorcycle displacement, and it turned out that the impacts on the severity were in the following order: a road alignment of left downhill, the type of motorcycle-to-vehicle accidents and a road alignment of a flatland on the left. The significance of the models was tested using the likelihood ratio, the level of significance and suitability statistics about them, and as a result of the test, the significance level and suitability of the constructed models were all excellent. In addition, the model accuracy indicating the accuracy of a predicted value compared to that of the value actually observed was 70.3% for minor injury; 70.1% for serious injury; and 68.6% for fatal injury, and the overall accuracy was 70.2%, which was very high. CONCLUSIONS : As a result of an analysis of motorcycle accidents in Seoul through the ordered probit model and the marginal effect, it turned out that their severity increased in nighttime accidents as compared to daytime ones and gradually increased in the order of motorcycle-to-vehicle accidents, motorcycle-to-person ones and the ones involving motorcycle only. As a result of an analysis, the severity of accidents in road alignments of left downhill, left flatland and straight downhill increased as compared to those in a road alignment of straight flatland and that the severity of accidents of motorcycles with a displacement larger than 50cc was higher than that of those with a displacement smaller than 50cc.

• 한국도로학회:학술대회논문집
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• 2011.03a
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• pp.77-84
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• 2011

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1997.11a
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• pp.65-68
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• 1997

화학공장에서 가연성물질의 누출로 인하여 발생한 화재ㆍ폭발사고는 공정시설의 파괴는 물론 근로자 및 인근지역의 주민들에게까지 치명적인 피해를 미칠 수 있으므로 이에 대한 체계적인 연구와 방지를 위한 적절한 대책의 마련이 반드시 필요하다. (중략)

• Journal of Families and Better Life
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• v.13 no.2
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• pp.45-55
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• 1995

본 연구는 1992 Health and Retirement Survey(HRS' the Beta Release)를 사용하여 유산상속 결정에 미치는 영향요인을 분석하였다 조사를 위해 사용된 표본은 55세이상의 노 인 2,208명이었으며 표본 특성을 파악하기 위해 평균과 빈도를 분석하였고 유산상속 결정에 미치는 영향요인을 조사하기 위해 Probit 분석을 수행하였다 분석결과 주택지분액이 클수록 저축.CD.채권.주식보유액이 많은 노인일수록 유산상속을 할가능성이 높게나타났다 또한 교육수준이 높거나 백인 노인의 경우는 교육수준이 낮거나 백인이 아닌 경우보다 유산상속 을 할 가능성이 높았다 반면 건강상태가 나쁘거나 자녀수가 많은 노인은 유산상속을 할 가 능성이 낮게 나타났다.

• Journal of Korea Technology Innovation Society
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• v.10 no.1
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• pp.1-21
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• 2007

Among numerous policy influencers' and researchers' advices and policy suggestions, there is little opposition to the proposition that technology is essential to the economic development. The role of technology has never been more emphasized than today in Korea as in any other countries. The effects of the government's innovation policy on corporate R&D activities and more broadly the economic welfare of a whole nation are widely recognized with intuitional and empirical evidence. That is, various R&D incentives reduce the marginal cost of a firm's R&D efforts, inducing as much increase of its R&D investment to result in a better chance to acquire target technology. This paper examines the impact of R&D incentives on the technological outcomes by analyzing individual firms' investment behaviors subject to the government's R&D incentive policies. An econometric model of technological outcomes is estimated on a project level with cross-sectional data. "Probit model" is employed for estimations. Special attention was given to the effectiveness of R&D programs by estimating policy impact by types of investment. The data were collected from 928 different R&D projects completed between 1987 and 1993. With the single equation approach, we were able to find that the structure of investment is a far more significant factor in technological outcomes than the total amount of investment. The analysis also shows that the two types of firms' matching investment, in-kind and cash, do not bear a complementary, but a substitutive relations to each other. It also reconfirms the proposition that R&D incentives increase firm's financial investment. Despite many supportive studies emphasizing the cooperation between innovation performers, it is also found that the larger the number of institutions involved in a project, the less likely it leads to a technological success, And meeting the proposed deadlines without postponing is estimated to be a good barometer to predict the outcome of an R&D project. Also the probabilities of success for major variables are represented for policy implications, after calculating marginal effects.

• Journal of Korean Society of Transportation
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• v.31 no.6
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• pp.53-66
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• 2013

The major purpose of this study is to evaluate methodologies to predict the injury severity of pedestrian-vehicle collisions. Methodologies to be evaluated and compared in this study include Binary Logistic Regression(BLR), Ordered Probit Model(OPM), Support Vector Machine(SVM) and Decision Tree(DT) method. Valuable insights into applying methodologies to analyze the characteristics of pedestrian injury severity are derived. For the purpose of identifying causal factors affecting the injury severity, statistical approaches such as BLR and OPM are recommended. On the other hand, to achieve better prediction performance, heuristic approaches such as SVM and DT are recommended. It is expected that the outcome of this study would be useful in developing various countermeasures for enhancing pedestrian safety.

• Journal of Korea Technology Innovation Society
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• v.13 no.3
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• pp.513-537
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• 2010

According to the "FDI-as-market-discipline" hypothesis, inward FDI acts as a mechanism of change in market structure affecting innovative activities of domestic firms. We used panel KIS data for testing this hypothesis. Binary probit estimation shows that, in contrast to the German case of Bertschek (1995), FDI is insignificant in Korean case for explaining product innovation. 1his result maybe comes from the fact that the industries in Korea are more monopolistic or oligopolistic than those of Germany. Using panel data, we tried random parameter estimation using matrix weighted average of GLS and OLS. The result shows different estimates from cross-section outcome and panel estimation with parameter homogeneity, so we can infer large parameter heterogeneity across firms. But, interpretation for FDI variable is similar across panel and cross-section estimation.

• Journal of Korea Technology Innovation Society
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• v.13 no.1
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• pp.124-139
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• 2010

This study analyzes determinants of innovation in Korea manufacturing industries from 2005 to 2007. In order to do this, we use raw data from 'Korea Innovation Survey 2008: Manufacturing Sector' conducted by STEPI, and also collect financial statement data from Korea Investors Service. As an analytical method for the empirical test, we utilize Probit model. Empirical results show that firm size and market concentration have positive relationship with firm's innovation activities. These support the ‘Schumpeterian hypothesis’. This would be the most distinguished feature of this study compared to previous literatures.Our study also shows that R&D personnel ratio, R&D intensity, and advertising intensity have positive effects on firms' innovation. Thus, we can say that R&D activities and consumer orientation are the main determinants of innovation. However, profit ratio and growth rate do not have any statistically significant effect on firms' innovation.

• Journal of Korean Society of Transportation
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• v.36 no.1
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• pp.13-22
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• 2018

Buses, one of the representative public transportation modes, are divided into a vareity of service types according to the purpose of operation, operating distance, and management agencies. Although bus-involved crashes may cause large amount of damage due to the higher number of passengers boarded on a bus, prior research has little focused on crash severity according to bus service types. This study aims to investigate factors influencing crash severity in bus-involved crashes and to present policy implications to reduce crash severity by bus service type. To do this, bus-involved crash data from the Traffic Accident Analysis System (TAAS) during five-year period are used. Ordered probit models for three types of bus service, i.e., city bus, suburban and express buses, and charter buses, are estimated to analyze the factors of accident severity. The results show that there are significant differences of factors affecting crash severity among the types of bus services while speed and road surface influence all the types of buses. In case of local buses, time of day, roadway alignment, and installation of a traffic signal are found to be statistically significant factors. Seat belt and road class have significant effects on injury severity of the intercity and express buses. Chartered buses have time of day, driving experience, seatbelt, traffic signal, and day of week as the significant factors. The results of this study are expected to contribute to the reduction of the crash severity by each bus service type.

• Environmental and Resource Economics Review
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• v.21 no.4
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• pp.893-920
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• 2012

This study is to investigate causal relationship between individual life satisfaction and air pollution, using ordered probit model with the KLIPS panel dataset for 1998-2008. As determinants, both individual economic and socio-demographic characteristics are considered. Empirical results show that the degree of air pollution has negative effects on individual life satisfaction. The effects of other variables are similar to those of existing studies. This study found that life satisfaction increases along with income increase. However, at a certain point, the increase of life satisfaction becomes smaller even with an increase in income, indicating non-linear effect. It implies that the Easterlin's paradox can be applied to Korea's case. The increase of the other person's income measured by income per capita in the region where respondent resides has negative effects on life satisfaction. On the other hand, a person who has married, own house, stayed healthy, and highly been educated is likely to have higher life satisfaction. Additionally, a person with many household members, urban resident, unemployed or self-employed are negatively correlated with life satisfaction.