• 제목/요약/키워드: Panel Data Models

검색결과 265건 처리시간 0.039초

조부모에 의한 비공식 자녀돌봄 및 지원이 기혼여성의 추가출산 계획에 미치는 영향: 패널분석 방법을 이용하여 (The effect of informal grandparent-provided child care and support on married women's additional birth plans: A panel data analysis)

  • 한영선;이연숙
    • 가족자원경영과 정책
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    • 제18권2호
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    • pp.163-182
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    • 2014
  • This study examined the effects of informal grandparent-provided child care and support on married women's additional birth plans. This study applied panel data analysis to three waves of the Korean Longitudinal Survey of Women and Family (KLoWF) and obtained two major findings, as follows. First, having a mother-in-law and co-residing with parents-in-law had a positive influence on married working women's additional birth plans. Child care provision from the parents of a married working woman also positively influenced her additional birth plans. Second, the analysis showed that housework assistance from a woman's mother-in-law or mother had no effect on her birth plans in both models investigated: the additional birth plan model for all women, both employed and unemployed, and the additional birth plan model for only working women. In conclusion, the findings of this study demonstrated that child care availability, with grandparents as the trusted providers, is a more important factor in married women's additional birth plans than housework assistance from their mothers-in-law and mothers.

Determinants of Profitability in Commercial Banks in Vietnam, Malaysia and Thailand

  • DAO, Binh Thi Thanh;NGUYEN, Dung Phuong
    • The Journal of Asian Finance, Economics and Business
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    • 제7권4호
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    • pp.133-143
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    • 2020
  • The paper investigates the factors affecting the profitability of commercial banks in Asian developing countries, including Vietnam, Malaysia and Thailand. We use panel data of four entities; ten banks in Vietnam, eight banks in Malaysia, nine banks in Thailand and all 27 commercial banks from the period 2012 to 2016. Particularly, Return on Asset, Return on Equity and TOBINQ are defined as profitability indicators, which are impacted by three main types of independent variables, namely bank-specifics, which include CAR, NPL, Cost to income, Liquidity ratio and Bank size, industry-specific variable-concentration HHI and macroeconomic-specific variables, which consist of GDP growth and Inflation. Using panel data regressions, the paper identifies several similarities and differences among empirical results on the models of four entities, each of three countries and the overall sample. The most outstanding similarity is that all entities record the significantly negative relationship between operational risk and banking profitability. Likewise, the significantly negative influence of bank size to profitability is found on models of Vietnam and Thailand and no significant effect on the model of Malaysia. Meanwhile, the most controversial result comes up with the negative relationship between CAR and profitability indicators as well as the positive association between credit risk and banking profitability.

실험적 정전용량 모델과 축적 용량 설계 방법에 따른 TFT-LCD 화소의 동작 특성 (Effects of an Empirical Capacitance Models and Storage Capacitance Types on TFT-LCD Pixel Operations)

  • 윤영준;정순신;박재우;최종선
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 D
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    • pp.1750-1752
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    • 1999
  • An active-matrix liquid crystal display (LCD) using thin film transistors (TFTs) has been widely recognized as having potential for high-quality color flat-panel displays. Pixel-Design Array Simulation Tool (PDAST) was used to profoundly understand the gate signal distortion and pixel charging capability, which are the most critical limiting factors for high-quality TFT-LCDs. Since PDAST can simulate the sate, data and pixel voltages of a certain pixel on TFT array at any time and at any location on an array, the effect of the new set of capacitance models on the pixel operations can be effectively analyzed. The set of models which is adopted from VLSI interconnections calculate more precise capacitance. The information obtained from this study could be utilized to design the larger area and finer image quality panel.

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EU ETS 실시 이후 탄소누출 가능성 산정 연구

  • 김수이
    • 자원ㆍ환경경제연구
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    • 제21권3호
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    • pp.519-542
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    • 2012
  • 본 논문은 EU ETS 기간 전과 후를 비교함으로써 탄소누출이 일어났는가를 실증적으로 분석하였다. 해외직접투자를 탄소누출의 지표로 활용하여 EU 11개국을 대상으로 한 1995년부터 2009년까지의 패널데이터를 이용하여 생산비용과 환경비용과의 패널 분석을 하였다. 시장 추구형 해외직접효과도 아울러 고려하여 해외시장잠재력도 아울러 고려하였다. 본 분석에 의하면 제조업을 대상으로 한 일부모형에서 탄소누출이 확인되었다. 하지만 다양한 모형에서 일관되게 확인되지 않아서 EU 배출권거래제를 전후하여 탄소누출이 뚜렷하게 일어났다고 단정하기는 힘들다. 비교적 데이터의 시계열이 짧음에도 불구하고 일부모형에서 탄소누출이 검증되었다는 사실을 볼 때 향후 국내 배출권거래제 도입시 우리나라도 탄소누출의 가능성을 염두에 두고 배출권거래제 제도를 설계해야 할 것이다.

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시간영역 랜킨 패널법에 의한 선박 부가저항의 수치해석 (Numerical Analysis of Added Resistance on Ships by a Time-domain Rankine Panel Method)

  • 김경환;김용환
    • 대한조선학회논문집
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    • 제47권3호
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    • pp.398-409
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    • 2010
  • This paper considers the numerical computation of added resistance on ships in the presence of incident waves. As a method of solution, a higher-order Rankine panel method is applied in time domain. The added resistance is evaluated by integrating the second-order pressure on the body surface. Computational results are validated by comparing with experimental data and other computational results on a hemi-sphere, a barge, Wigley hull models, and Series 60 hull, showing very fair agreements. The study is extended to the comparison between Neumann-Kelvin and double-body linearization approaches, and their differences are discussed.

재고-신규주택 상대가격이 주택공급에 미치는 영향 (The Impact of Stock-to-Flow Price Ratio on Housing Starts)

  • 지규현;최성호
    • 토지주택연구
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    • 제11권1호
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    • pp.59-66
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    • 2020
  • This thesis investigates relationship between Stock-to-Flow price and housing starts in Seoul metropolitan form 2008 year to 2019 year. The paper tests the relationship through two time-series models such as a vector error correction model and Dynamic Panel regression model. The model results show evidence of positive correlation between Stock-to-Flow price and housing starts in the long run. By transforming the regional data into a panel data set and running a fixed effects model, we test the explanatory power of PBR on housing starts. The result of VECM confirms that one unit uprising PBR raises up apartment construction by 7.4%. This result supports that PBR is a major factor in choosing a start of housing construct. Base on the result of empirical model, We also suggest that the market self-regulation function of housing providers is operating in the entire metropolitan area market.

Decomposition and Super-efficiency in the Korean Life Insurance Industry Employing DEA

  • Lee, Hyung-Suk;Kim, Ki-Seog
    • International Journal of Contents
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    • 제4권3호
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    • pp.1-9
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    • 2008
  • The Korean life insurance industry has undergone profound changes, such as the beginning of the variable insurance in July 2001 and the bancassurance enforcement in August 2003. However, little empirical research has analyzed data that includes the bancassurance of life insurance companies operating in Korea. In response to this lack of research, this paper applies DEA (data envelopment analysis) models to measure and decompose their efficiency. We discovered that life insurance companies operating in Korea are a little different in their composition ratio of inputs and outputs, due to the increased variety of distribution channels and new products. We provided efficiency scores, return to scale, and reference frequencies. We also decomposed CCR, BCC, and SBM efficiency into scale efficiency and MIX efficiency. So, we try to investigate whether the sources of inefficiency were caused by the inefficient operation of DMU, disadvantageous conditions, the difference of the composition ratio in inputs and outputs with reference sets, or any combination of the above. Most companies in the sample display had either constant or decreasing returns to scale. The efficiency rankings were less consistent among models and efficient DMUs. In response to this problem, we used the super-efficiency model to rank them and then compared the rankings of the DMUs among the various models. It was also concluded that the availability of panel data, rather than cross-sectional data, would greatly improve the validity of the efficiency estimates.

Numerical simulation of hollow steel profiles for lightweight concrete sandwich panels

  • Brunesi, E.;Nascimbene, R.;Deyanova, M.;Pagani, C.;Zambelli, S.
    • Computers and Concrete
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    • 제15권6호
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    • pp.951-972
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    • 2015
  • The focus of the present study is to investigate both local and global behaviour of a precast concrete sandwich panel. The selected prototype consists of two reinforced concrete layers coupled by a system of cold-drawn steel profiles and one intermediate layer of insulating material. High-definition nonlinear finite element (FE) models, based on 3D brick and 2D interface elements, are used to assess the capacity of this technology under shear, tension and compression. Geometrical nonlinearities are accounted via large displacement-large strain formulation, whilst material nonlinearities are included, in the series of simulations, by means of Von Mises yielding criterion for steel elements and a classical total strain crack model for concrete; a bond-slip constitutive law is additionally adopted to reproduce steel profile-concrete layer interaction. First, constitutive models are calibrated on the basis of preliminary pull and pull-out tests for steel and concrete, respectively. Geometrically and materially nonlinear FE simulations are performed, in compliance with experimental tests, to validate the proposed modeling approach and characterize shear, compressive and tensile response of this system, in terms of global capacity curves and local stress/strain distributions. Based on these experimental and numerical data, the structural performance is then quantified under various loading conditions, aimed to reproduce the behaviour of this solution during production, transport, construction and service conditions.

선박의 파랑 중 부가저항에 대한 실험과 수치계산의 비교 연구 (Systematic Experimental and Numerical Analyses on Added Resistance in Waves)

  • 박동민;서민국;이재훈;양경규;김용환
    • 대한조선학회논문집
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    • 제51권6호
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    • pp.459-479
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    • 2014
  • This paper considers experimental and numerical studies on added resistance in waves. As the numerical methods, three different methods, strip method, Rankine panel method and Cartesian-grid method, are applied. The computational results of vertical motion response and added resistance are compared with the experimental data of Series 60($C_B=0.8$) hull, S175 containership and KVLCC2 hull. To investigate the influence of above-still water hull form, a Rankine panel method is extended to two nonlinear methods: weakly-nonlinear and weak-scatterer approaches. As nonlinear computational models, three ships are considered: original KVLCC2 hull, 'Ax-bow' and 'Leadge-bow' hulls. Two of the three models are modified hull forms of original KVLCC2 hull, aiming the reduction of added resistance. The nonlinear computational results are compared with linear results, and the improvement of computational result is discussed. As experimental approach, a series of towing-tank experiment for ship motions and added resistance on the three models (original KVLCC2 hull, 'Ax-bow' and 'Leadge-bow') are carried out. For the original KVLCC2 hull, uncertainty analysis in the measurement of vertical motion response and added resistance is performed in three waves conditions: ${\lambda}/L=0.5$, 1.1, 2.0. From the experimental results, the effects of hull form on added resistance are discussed.

중선형 모형을 이용한 비선형 시계열 패널자료의 동질성검정에 대한 연구 (A Study on the Test of Homogeneity for Nonlinear Time Series Panel Data Using Bilinear Models)

  • 김인규
    • 디지털융복합연구
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    • 제12권7호
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    • pp.261-266
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    • 2014
  • 시계열 모형에서 모수의 수가 많으면 모수추정에 따르는 오차가 커지게 되므로 예측을 하는데 많은 어려움이 있다. 만약 여러개의 시계열 자료들이 동일한 모형에서부터 얻어졌다고 하는 동질성 가설이 채택되면 모수축약을 이룰 수 있고, 더 좋은 예측값을 얻을 수 있다. 비선형 시계열 패널 자료는 각각의 시계열마다 모수들이 있기 때문에 매우 많은 모수가 존재하게되고, 모수의 수가 많으면 모수추정에 따르는 오차가 커지게 되어 예측의 정확도가 떨어지게 된다. 패널내에 존재하는 독립적인 여러 시계열들의 동질성이 만족되면 시계열을 종합하여 모수를 추정하고 검정할 수 있다. m개의 독립적인 비선형 시계열 패널 자료의 동질성 검정을 알아보기 위하여 모형을 설정하고 이 모형에 대한 정상성 조건을 구하였고, 동질성 검정통계량을 유도했으며, 구한 검정 통계량의 극한분포가 ${\chi}^2$ 분포를 따르는 것을 보였다. 실증분석에 있어서는 비선형 시계열 자료중 중선형 시계열 모형의 동질성 검정을 하고, 실제 우리나라 주식자료를 2개의 집단으로 나누어 비선형 시계열 패널 자료의 동질성 검정에 대한 분석을 하였다.