• Title/Summary/Keyword: Panel Data Models

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The Impact of National Innovation Capabilities and Institutional Quality on Economic Growth (국가혁신역량과 제도의 질이 경제성장에 미치는 영향)

  • Cho, Hyeongrye;Chung, Sunyang
    • Journal of Technology Innovation
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    • v.23 no.4
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    • pp.33-61
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    • 2015
  • The global economy is rapidly changing by technological innovation and diffusion of knowledge across nations. Therefore it is still important issue to find a major variables for convergence and divergence of economic development. The studies up to present on the relationship between innovation and institution has limitations that they have dealt with this issue only in term of cross-sectional study or mathematical research models. This paper aims at analyzing the impact of innovation capabilities and institutional quality on the economic growth. Empirically this paper will explore the relationship among human capital capacity and FDI, R&D expenditures and innovation capabilities and institutional quality. This paper analyzes 64 countries, which were divided into 4 groups depending on the level of economic development. Based on the data from 1995 to 2011 and by using a panel model, we look at the structural implications of the research questions. According to our analysis, the weight of R&D and the innovation capabilities were identified as important determinants of economic growth, and FDI was significant factor for economic growth in the upper middle group countries. In case of the innovation capabilities of countries, the diffusion and openness of innovation were most meaningful variables for economic growth. Also, institutional quality has a significantly positive impact. However, in the low-level economic group, innovation capabilities and institutions have a negative impact on economic growth. This paper identifies an important policy implications that of national innovation and institutional factors should be properly invested in accordance with the level of a country's economic growth.

Changes in Physical and Mental Health as a Function of Substandard Housing Conditions and Unaffordable Housing (주거빈곤이 건강에 미치는 영향에 관한 종단연구)

  • Park, Jungmin;Heo, Yongchang;Oh, Ukchan;Yoon, Sookyung
    • Korean Journal of Social Welfare
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    • v.67 no.2
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    • pp.137-159
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    • 2015
  • This longitudinal study examined the influence of substandard housing conditions and housing affordability on physical and mental health. Using data from the Korea Welfare Panel Study, this study followed 8,583 adults who continued to participate in the survey from 2009 to 2013. Multivariate analyses involved linear and logistic regression models with the hybrid method that incorporates both fixed and random effects. Results show that substandard housing conditions and excess housing cost burden had significant adverse effects on adults' mental health (e.g., depressive symptoms). About one fourth of the entire sample and one third of those in poverty reported having lived in substandard housing conditions. Additionally, nearly one fourth of those in poverty reported having experienced excess housing cost burden, which is 4 times greater than that of the entire sample. Our findings show that a substantial proportion of individuals, particularly among the poor, have a difficulty in accessing to decent, affordable housing, and that housing assistance may have additional benefits of improving the mental health of individuals with housing issues.

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The Effect of Child Neglect and Abuse by Parents on School Adjustment of School-Aged Children : The Mediating Effects of Self-Awareness and Peer Attachment (부모의 방임·학대가 학령기 아동의 학교생활적응에 미치는 영향: 학령기 아동의 자아인식과 또래애착의 매개효과)

  • Kim, Hye Gum;Jo, Hye Young
    • Korean Journal of Childcare and Education
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    • v.12 no.1
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    • pp.19-36
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    • 2016
  • The purpose of the present study was to investigate the effect of child neglect and abuse by parents on school adjustment of school-aged children focusing on mediating effect of school-aged children's self-awareness and peer attachment. For this purpose, we analyzed the data of fourth wave Korean Child-Youth Panel Survey(KCYPS) including parents' child neglect and abuse, school-aged children's school adjustment, self-awareness and peer attachment. A total of 2,378 children and their parents using structural equation model of mediating effects responded to the survey. Measurement model and structure model had favorable goodness of fit and the results of structure models on each path were as follows. First, school-aged children's school adaption had negative correlations with parent's child neglect and abuse, but positive correlations with their self-awareness and peer attachment. Second, parent's child neglect and abuse influenced on school-aged children's school adjustment by partial mediators, their self-awareness and peer attachment. These findings showed practical way to increase school-aged children's self-awareness and positive peer attachment.

Multiscale modeling of reinforced/prestressed concrete thin-walled structures

  • Laskar, Arghadeep;Zhong, Jianxia;Mo, Y.L.;Hsu, Thomas T.C.
    • Interaction and multiscale mechanics
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    • v.2 no.1
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    • pp.69-89
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    • 2009
  • Reinforced and prestressed concrete (RC and PC) thin walls are crucial to the safety and serviceability of structures subjected to shear. The shear strengths of elements in walls depend strongly on the softening of concrete struts in the principal compression direction due to the principal tension in the perpendicular direction. The past three decades have seen a rapid development of knowledge in shear of reinforced concrete structures. Various rational models have been proposed that are based on the smeared-crack concept and can satisfy Navier's three principles of mechanics of materials (i.e., stress equilibrium, strain compatibility and constitutive laws). The Cyclic Softened Membrane Model (CSMM) is one such rational model developed at the University of Houston, which is being efficiently used to predict the behavior of RC/PC structures critical in shear. CSMM for RC has already been implemented into finite element framework of OpenSees (Fenves 2005) to come up with a finite element program called Simulation of Reinforced Concrete Structures (SRCS) (Zhong 2005, Mo et al. 2008). CSMM for PC is being currently implemented into SRCS to make the program applicable to reinforced as well as prestressed concrete. The generalized program is called Simulation of Concrete Structures (SCS). In this paper, the CSMM for RC/PC in material scale is first introduced. Basically, the constitutive relationships of the materials, including uniaxial constitutive relationship of concrete, uniaxial constitutive relationships of reinforcements embedded in concrete and constitutive relationship of concrete in shear, are determined by testing RC/PC full-scale panels in a Universal Panel Tester available at the University of Houston. The formulation in element scale is then derived, including equilibrium and compatibility equations, relationship between biaxial strains and uniaxial strains, material stiffness matrix and RC plane stress element. Finally the formulated results with RC/PC plane stress elements are implemented in structure scale into a finite element program based on the framework of OpenSees to predict the structural behavior of RC/PC thin-walled structures subjected to earthquake-type loading. The accuracy of the multiscale modeling technique is validated by comparing the simulated responses of RC shear walls subjected to reversed cyclic loading and shake table excitations with test data. The response of a post tensioned precast column under reversed cyclic loads has also been simulated to check the accuracy of SCS which is currently under development. This multiscale modeling technique greatly improves the simulation capability of RC thin-walled structures available to researchers and engineers.

Valuing Non-market Benefits of Water Quality Improvements in Paldang Reservoir and Han River : A Choice Experiments Study (팔당호 및 한강 수질개선의 비시장가치 측정 - 속성가치선택법을 이용하여 -)

  • Kim, Yong-Joo;Yoo, Young Seong
    • Environmental and Resource Economics Review
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    • v.14 no.2
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    • pp.337-379
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    • 2005
  • This choice experiments study values the non-market benefits of water quality improvements in Paldang Reservoir and Han River, located in Korea. A fractional factorial orthogonal design was used to produce four different choice sets per respondent, before employing choice examples to screen out irrational responses. The panel mixed logit model (with normal distributions for the attributes) fit the data best, indicating that allowing for both heterogeneous preferences across households and correlation between repeated choices may represent actual choice behaviors best of all the estimated models. The significant standard deviations of the random attributes suggest that the taste for each attribute may vary considerably in the population. The annual benefits to the Seoul Metropolitan area for a small (large) enhancement of the clarity of water, a gradual removal of unpleasant waters, and a gradual improvement in biodiversity, were estimated to be some 1.5 trillion (1.7 trillion) Won, 2 trillion Won, and 1.7 trillion Won, respectively, with 1.8~2.6 trillion Won for at least two of them occurring together. The study also discusses potential biases germane to choice experiments studies of this type.

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Contemporary Financial Profile and Its Implications on the Level of Corporate Cash Holdings for Korean Chaebol Firms (한국 재벌기업들의 현금유동성 수준 결정요인과 재무적 분석)

  • Kim, Hanjoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.6
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    • pp.3870-3881
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    • 2015
  • This study examined one of the contemporary issues on debate to identify any significant financial determinants on the cash holdings of the cheabol firms in the Korean domestic capital markets. Several important findings on the financial characteristics affecting the cash holdings were evidenced by utilizing various methodologies for statistical estimations. Financial or managerial implications with discussion were provided for the pronounced factors such as CASHFLOW, MVBV, REINVEST, and AGENCY. Assuming that the chaebol firms were overall subject to the financial constrains, they may increase or stockpile cash reserves as internal capital for future investment opportunities or repayment of existing debt, rather than external financing burdened by a high cost of capital. Given the on-going controversy on the optimal level of corporate cash holdings coupled with any foreseeable capital transfer among the associated nations through the investment vehicles such the FTAs (Free Trade Agreements) or TPP (Trans-Pacific Pacts), any empirical findings of the study may shed new light on identifying financial determinants which may significantly affect the level of cash holdings for the business conglomerates, the 'chaebol' firms, in the Korean capital markets.

Inequalities in Self-rated Health among Middle-aged and Young-old Waged Workers: The Contribution of Precarious Employment and Social Capital (중고령기에서 초기노년기에 걸친 주관적 건강상태의 격차: 고용형태와 사회적 자본의 효과를 중심으로)

  • Ahn, Joonhee
    • 한국노년학
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    • v.37 no.3
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    • pp.727-745
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    • 2017
  • This study purported to examine the effects of precarious employment and social capital on the changes of self-rated health status among the middle aged and the young-old population in South Korea. The study analyzed 12 year follow-up data generated by the Korean Labor and Income Panel Study(KLIPS 6-17), which included 10532 employed subjects aged 55 to 75. Multi-level growth curve modeling was performed by fixed and random effect models using STATA 13.0 program. Afterwards, Hausman test was performed, which resulted in support of the estimation by fixed effect model. The results showed that a day labor position was significant factor affecting the deteriorated changes of self-rated health status over time. In addition, wage, weekly working hours, and private/relational social capitals were also found to be significant factors affecting the changes of the self-rated health status. The results supported the divergence hypothesis as well as the cumulative advantage theory. Efforts should be made to develop and implement various employment support policies and social service programs to alleviate the health inequality of the employed workers over their middle-aged to young-old period.

The Effects of the Number, Ratio of Advanced Courses, and Variety in Science Elective Subjects on the Growth of High School Science Course Students' Attitude Towards Science (고등학교에서 과학 선택 과목의 수, 심화(II) 과목 비율, 교과 다양성이 이과 학생의 과학에 대한 태도 성장에 미치는 효과)

  • Lee, Gyeong-Geon;Hong, Hun-Gi
    • Journal of Science Education
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    • v.46 no.1
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    • pp.80-92
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    • 2022
  • We fitted latent growth models of attitude towards science using the Korea Education & Employment Panel 2004-2007 data with 343 high school students. The growth model show better fit indices compared to the no growth model. The intercept and slope showed significant variances, and thus, we added control variables of the number, ratio of advanced courses, and variety in science elective subjects, and the achievement percentile for middle school. In the conditional growth model, the previous achievement has significant positive effects on the intercept and the ratio of the advanced courses and variety of science subjects show significantly positive effects on the slope. Based on the results, it supports the 2022 Revised Science Curricular that high school credit system should provide students with basic 'Physics,' 'Chemistry,' 'Biology,' and 'Earth Science,' credits in 'general electives', various integrated subjects in 'converged electives', and highly advanced subjects in 'career electives.'

An Exploratory Study upon The Factors for Discriminating Generations: Focusing on Welfare Attitudes Values on Social Issues (한국인의 세대 판별요인에 대한 탐색적 연구: 복지태도와 가치관을 중심으로)

  • Sin-Young Kim
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.4
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    • pp.169-174
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    • 2024
  • This study purports to identify the factors that contribute to the classification of age groups or generations of Koreans. Independent variables such as respondents' attitudes toward welfare, attitudes toward equity, education level, perception of inequality in Korean society, tax awareness, and health status are included in the model that were put into the analysis with the main interest. Since this study does not construct any hypothesis prior to analysis, the nature of this study can be said exploratory. The data utilized for the analysis are from the 17th year of the Korean Welfare Panel collected in 2022, and a linear discrimination analysis technique will be used. First and foremost, a theoretical review of the generational classification will be conducted through domestic and international literature in the past. To date, there is no quantitative studies in Korea that have a significant influence on the generational classification. Therefore, in this study, a theoretical review of political tendencies and values, which are estimated to have a significant influence on the generational classification, that is, the difference between generations, will be significant. The perception and attitude toward welfare will be discussed in the review of values. Next, analysis models, analysis techniques, and variables to be used in the analysis will be introduced. After

The Effects of Technology Innovation and Employment on Start-ups' Credit Ratings: Asymmetric Information Hypothesis vs Competence Hypothesis (기술혁신 활동과 고용 수준이 소규모 창업기업에 대한 신용평가에 미치는 영향: 비대칭적 정보 가설 vs. 역량 가설)

  • Choi, Young-Cheol;Yang, Taeho;Kim, Sunghwan
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.15 no.2
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    • pp.193-208
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    • 2020
  • In this study, we investigate the effects of technology innovation investments and employment on credit ratings of very small start-up businesses using the data period of 2009 till 2015 test two hypotheses: asymmetric information hypothesis or competence hypothesis. We use financial and non-financial data of 51,903 observations of 12,028 small businesses from a database of a commercial bank and fixed effects panel models and two-stage instrumental variable models. We find that in the short-run small size startups show lower credit ratings than non-startups, and that both technology innovation activities and employment capability improve their credit ratings. In the long-run, technology innovation investments do not improve their credit ratings of later years while employment capability improve their credit ratings of the subsequent year. In addition, the age of startups improves their credit ratings of the current year and until the subsequent two years while employee productivity, fixed ratio and ROA positively affect their credit ratings for up to three years. However, short-term and overall debt ratios, cost of borrowings and firm-size negatively affect their credit ratings for up to three years. The results of the study on credit ratings suggest that credit rating agencies seem to consider both technology innovation activities and employment capability in the credit ratings of small start-ups as 'competence factors' rather than 'asymmetric information factors' with inefficiency and cost burdens. The results also suggest that we must find ways to reflect properly the severe asymmetric information of the early-stage start-ups, and technology innovation activities and employment capability in the credit rating formula.