• 제목/요약/키워드: panel estimation

Search Result 405, Processing Time 0.024 seconds

패널 VAR 모형을 이용한 지역별 양식넙치 산지가격의 동태적 인과관계 분석 (A Dynamic Causality Analysis of Oliver Flounder Producer Price by Region using the Panel VAR Model)

  • 전용한;남종오
    • 수산경영론집
    • /
    • 제52권1호
    • /
    • pp.47-63
    • /
    • 2021
  • The purpose of this study is to identify the leading price between Jeju and Wando's oliver flounder producer price and to analyze the dynamic effect of the regional producer price using the panel VAR model. In the process of analysis, it was confirmed that there are unit roots in the monthly data of Jeju and Wando's oliver flounder producer price. So, in order to avoid spurious regression, the rate change of producer price which carries out log difference was used in the analysis. As a result of the analysis, first, the panel Granger causality test showed that the influence of the change rate of producer price in oliver flounder in Jeju was slightly larger than that in Wando, but it was found that each region all leads the change rate of the producer price in oliver flounder. Second, the panel VAR estimation showed that the rate change of producer price in Jeju and Wando a month ago had a statistically significant effect on the change rate of producer price of each region. Third, the impulse response analysis indicated that other regions are affected a little more than the same region in case of the occurrence of the impact on the error terms of the change rate of produce price in Jeju and Wando oliver flounder. Fourth, the variance decomposition analysis showed that the change rate of producer price in the two regions was higher explained by Jeju compared to Wando. In conclusion, it is expected that the above results can not only be useful as basic data for the stabilization of oliver flounder producer price and the establishment of policies for easing volatility but can also help the oliver flounder industry operate its business.

기온을 이용한 무 생산량 패널분석 (Panel analysis of radish yield using air temperature)

  • 김용석;심교문;정명표;최인태
    • 농업과학연구
    • /
    • 제41권4호
    • /
    • pp.481-485
    • /
    • 2014
  • According to statistical data the past ten years, cultivation area and yield of radish are steadily decreasing. This phenomenon cause instability of radish's supply due to meteorological chage, even if radish's yield per unit area is increasing by cultivation technological development. These problems raise radish's price. So, we conducted study on meteorological factors for accuracy improvement of radish yield estimation. Panel analysis was used with two-way effect model considering group effect and time effect. As the result, we show that mixed effects model (fixed effect: group, random effects: time) was statistical significance. According to the model, a rise of one degree in the average air temperature on August will decrease radish's yield per unit area by $428kg{\cdot}10a^{-1}$ and that in the average air temperature on October will increase radish's yield per unit area by $438kg{\cdot}10a^{-1}$. The reason is that radish's growth will be easily influenced by meteorological condition of a high temperature on August and by meteorological condition of a low temperature on Octoboer.

Shear strength model for reinforced concrete corbels based on panel response

  • Massone, Leonardo M.;Alvarez, Julio E.
    • Earthquakes and Structures
    • /
    • 제11권4호
    • /
    • pp.723-740
    • /
    • 2016
  • Reinforced concrete corbels are generally used to transfer loads within a structural system, such as buildings, bridges, and facilities in general. They commonly present low aspect ratio, requiring an accurate model for shear strength prediction in order to promote flexural behavior. The model described here, originally developed for walls, was adapted for corbels. The model is based on a reinforced concrete panel, described by constitutive laws for concrete and steel and applied in a fixed direction. Equilibrium in the orthogonal direction to the shearing force allows for the estimation of the shear stress versus strain response. The original model yielded conservative results with important scatter, thus various modifications were implemented in order to improve strength predictions: 1) recalibration of the strut (crack) direction, capturing the absence of transverse reinforcement and axial load in most corbels, 2) inclusion of main (boundary) reinforcement in the equilibrium equation, capturing its participation in the mechanism, and 3) decrease in aspect ratio by considering the width of the loading plate in the formulation. To analyze the behavior of the theoretical model, a database of 109 specimens available in the literature was collected. The model yielded an average model-to-test shear strength ratio of 0.98 and a coefficient of variation of 0.16, showing also that most test variables are well captured with the model, and providing better results than the original model. The model strength prediction is compared with other models in the literature, resulting in one of the most accurate estimates.

시각 장치를 사용한 조선 소조립 라인에서의 용접부재 위치 인식 (Position Estimation of the Welding Panels for Sub-assembly line in Shipbuilding by Vision System)

  • 노영준;고국원;조형석;윤재웅;전자롬
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1997년도 춘계학술대회 논문집
    • /
    • pp.719-723
    • /
    • 1997
  • The welding automation in ship manufacturing process,especially in the sub-assembly line is considered to be a difficult job because the welding part is too huge, various, unstructured for a welding robot to weld fully automatically. The weld orocess at the sub-assembly line for ship manufacturing is to joint the various stiffener on the base panel. In order to realize automatic robot weld in sub-assembly line, robot have to equip with the sensing system to recognize the position of the parts. In this research,we developed a vision system to detect the position of base panle for sub-assembly line is shipbuilding process. The vision system is composed of one CCD camera attached on the base of robot, 2-500W halogen lamps for active illumination. In the image processing algorithm,the base panel is represented by two set of lines located at its two corner through hough transform. However, the various noise line caused by highlight,scratches and stiffener,roller in conveyor, and so on is contained in the captured image, this nosie can be eliminated by region segmentation and threshold in hough transform domain. The matching process to recognize the position of weld panel is executed by finding patterns in the Hough transformed domain. The sets of experiments performed in the sub-assembly line show the effectiveness of the proposed algorithm.

  • PDF

수상 태양광발전 시스템의 풍력계수 산정에 관한 실험적 연구 (An Experimental Study on the Estimation of Wind Force Coefficient of Floating Type Photovoltaic Energy Generation System)

  • 이영근;이남형;주형중;윤순종
    • 신재생에너지
    • /
    • 제9권1호
    • /
    • pp.60-68
    • /
    • 2013
  • In recent years, green house effect related natural disasters occur throughout the world. Carbon dioxide, mainly comes from the fossil fuel burning, is suspected to be the cause of green house effect. To reduce the emission of carbon dioxide, we need to find alternative energy resources such as photovoltaic energy. In this paper, the basic characteristics of wind force coefficient on a PV panel installed on the floating type PV energy generation system are investigated though the two-dimensional wind tunnel tests. Test variables included the angle of PV panel, direction of wind, number of rows of PV panel and attached or not attached frame. Based on the results obtained through the wind tunnel tests, it was found that the wind force coefficient can be used as a preliminary data in the design of the structure.

Stochastic Frontier Analysis를 이용한 제약회사의 효율성과 그 결정요인분석 (An Analysis on the Determinants of Efficiency of the Pharmaceutical Firms using Stochastic Frontier Analysis)

  • 사공진;김정규
    • 보건행정학회지
    • /
    • 제25권2호
    • /
    • pp.97-106
    • /
    • 2015
  • Background & Methods: The purpose of this research is to estimate the efficiency of the pharmaceutical firms and the determinants of their efficiency. Stochastic frontier analysis(SFA) and panel study are applied to the data of 60 domestic pharmaceutical firms from 2006 to 2012. Results & Conclusion: First, the result of the stochastic frontier analysis shows that overall efficiency of the pharmaceutical firms is increasing as time goes by. However, if firms are classified by the scale, the larger firms show more efficiency and if classified by the degree of innovativeness, the innovative firms show more efficiency compared to the non-innovative firms. This evidences show that the scale and R&D investment have significant relationships with the efficiency of the pharmaceutical firms. Therefore, it is necessary to increase the national level of investment for the fundamental researches to vitalize R&D of the new drugs. Second, the result of estimation of the determinants of efficiency shows that the firms with larger sales promotion expenses and entertainment expenses have less efficiency compared to the other firms. This can be explained by the structural characteristics of the small generic pharmaceutical firms. Therefore, the government had better make the pharmaceutical firms to reduce sales promotion and entertainment expenses and increase R&D expenses by introducing systems such as global budgeting system on medicine or reference pricing system.

한국의 서비스화에 대한 연구: Baumol 가설을 중심으로 (A Study on Tertiarization in Korea: Test of Baumol's Hypothesis)

  • 서환주;이영수
    • 한국산학기술학회논문지
    • /
    • 제8권1호
    • /
    • pp.143-150
    • /
    • 2007
  • 본 연구는 우리나라 서비스화의 특징을 분석하기 위하여 서비스화에 대한 유력한 설명인 수요편향가설 및 Baumol 가설을 우리나라 경험과 비교하였다. 이를 위하여 Baumol의 모형을 확장하여 패널 GMM방식으로 고용함수를 추정하였다. 분석결과를 요약하면 다음과 같다. 첫째, Clark의 수요편향가설을 살펴보기 위하여 1인당 GDP증가와 서비스고용간의 상관관계를 살펴본 결과 서비스화에 있어 소득증가가 절대적인 역할을 수행한다는 Clark의 수요편향가설을 우리나라의 경우에도 확인할 수 있었다. 둘째, 서비스화에 있어서 생산성격차를 강조하는 Baumol의 가설은 도소매, 음식 및 숙박서비스를 제외하고 모든 서비스분류에서 확인할 수 있었다. 즉 제조업과 각 서비스산업의 노동생산성격차가 확대될수록 서비스업의 고용이 증가한다는 사실을 우리나라의 경우에도 확인할 수 있었다.

  • PDF

Robustness of Cash Flow Value: Investment in ASEAN

  • LAU, Wei Theng;MAHAT, Fauziah Binti
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제6권2호
    • /
    • pp.247-255
    • /
    • 2019
  • This study examines the different roles of cash flow in assessing investment returns in the Association of Southeast Asian Nations (ASEAN). The analysis covers over 900 listed firms across Malaysia, Indonesia, Philippines, Singapore and Thailand for the period post the Asian financial crisis of 2001-2017. Firm-level panel data analysis shows that cash flow factors are important in all contexts of cash return on assets, earnings quality and market value multiple across the region even after controlling for typical measures of profitability. The results suggest that firms should manage cash flow prudently in considerations of firm value from the shareholder's perspective, measured directly using stock return. Cash profitability on assets should become an important firm performance indicator, whilst higher cash component over reported earnings is preferred. The market also tends to respond favourably to cash flow yield as a price multiple in valuation, outpacing the role of earnings yield. Such findings are robust across the pre and post subprime crisis periods, across estimation methods pertaining to finance panel standard errors, as well as across static and dynamic considerations of returns. It is hence sensible to consider cash flow factors in the research pertaining to asset pricing and factor investing in the ASEAN region.

International Logistics: Does It Matter in Foreign Trade?

  • HE, Yugang;CHOI, Baek-Ryul;WU, Renhong;WANG, Yinhui
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제8권2호
    • /
    • pp.453-463
    • /
    • 2021
  • Economic globalization provides a good channel for the development of foreign trade around the world. Due to this background, this paper sets the Organization for Economic Co-operation and Development (OECD) countries as a sample to explore the importance of international logistics in foreign trade. An annual panel data from 2000 to 2017 will be used to conduct an empirical estimation under the panel unit root test and the fixed effect model. Foreign trade is treated as an explained variable and international logistics is treated as explanatory variables. The findings show that international logistics have a positive spillover effect on export trade and the speed of international logistics development has a regulatory effect on the relationship between both of them, which presents a U-shaped curve. When the speed of international logistics development is slow, an increase of it restrains the positive spillover effect of international logistics on export trade. However, when it rises to a certain extent, this increase releases the positive spillover effect of international logistics on export trade. As can be seen by the evidence that this paper provides, the impact of international logistics on foreign trade is dynamic. Moreover, this paper also puts forward some corresponding measures about the relationship between both of them.

Analysis of Local Tax Performance Through Tax Capacity and Tax Effort in Indonesia 2014-2018

  • RAFSANJANI, Ali Hadi;AGUSTINA, Neli
    • Asian Journal of Business Environment
    • /
    • 제12권2호
    • /
    • pp.43-53
    • /
    • 2022
  • Purpose: This study aims to analyze the performance of local taxes in Indonesia through the estimation of tax capacity and tax effort, as well as classifying provinces based on the estimated value of tax capacity and tax effort. Research design, data and methodology: this study uses panel data of 34 provinces in Indonesia for the period of 2014-2018. The analytical method used in the tax capacity model is panel data regression to explain the factors that influence tax performance. Tax effort is estimated by the ratio of tax to tax capacity. Results: The results of the analysis show that gini ratio and regional expenditures have a significant positive effect on the tax ratio, while the share of GRDP in the manufacturing sector and HDI has a significant negative effect on the tax ratio. Based on the results, there are 19 provinces that have low tax capacity and 16 provinces that have low tax effort. Conclusions: The development of local tax performance tends to fluctuate with an average of 1.24 percent per year. Gini ratio and regional expenditure have a significant positive effect on the tax ratio, while the share of GRDP in the manufacturing sector and HDI have a significant negative effect on the tax ratio.