• 제목/요약/키워드: Regression estimator

검색결과 312건 처리시간 0.027초

Determinants of Middle Managers' Leadership in the Vietnamese Economic-Defense Enterprises

  • HOANG, Cuong Van;NGUYEN, Ngoc Huu;NGUYEN, Loan Quynh Thi;TRAN, Manh Dung
    • The Journal of Asian Finance, Economics and Business
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    • 제7권8호
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    • pp.543-553
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    • 2020
  • The purpose of this study is to investigate factors affecting the leadership capacity of middle managers and then evaluate the corresponding effect on the performance of subordinates in Vietnamese economic and defense enterprises. Data for the study was collected from questionnaire survey of 15 economic and defense enterprises, preceded by in-depth interviews with respondents who are subordinates of the departments/divisions of these enterprises. The research used logistic regression estimator to address econometric issues and to improve the accuracy of the regression coefficients. Our results show that the determinants of the leadership capacity of mid-level managers in defense and economic enterprises include: (i) personal qualities and qualities of managerial officials (understanding, courage), fairness, assertiveness and compliance), and leadership behaviors of two leadership styles - (ii) a transforming leadership style (influenced by ideals, inspirations, concerns) subordinates, stimulating intellect) and (iii) transactional leadership style (rewarding, detecting and handling problems for subordinates). Based on these results, our study suggests that middle managers should possess superior knowledge, care more about subordinates, understand the strengths and weaknesses of each subordinate, always be creative, assertive and courageous people as well as have high standards of competency and morality in order to become outstanding leaders in Vietnamese economic and defense enterprises.

Variation of Hydro-Meteorological Variables in Korea

  • Nkomozepi, Temba;Chung, Sang-Ok;Kim, Hyun-Ki
    • Current Research on Agriculture and Life Sciences
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    • 제32권3호
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    • pp.135-143
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    • 2014
  • The variability and temporal trends of the annual and seasonal minimum and maximum temperature, rainfall, relative humidity, wind speed, sunshine hours, and runoff were analyzed for 5 major rivers in Korea from 1960 to 2010. A simple regression and non-parametric methods (Mann-Kendall test and Sen's estimator) were used in this study. The analysis results show that the minimum temperature ($T_{min}$) had a higher increasing trend than the maximum temperature ($T_{max}$), and the average temperature increased by about $0.03^{\circ}C\;yr.^{-1}$. The relative humidity and wind speed decreased by $0.02%\;yr^{-1}$ and $0.01m\;s^{-1}yr^{-1}$, respectively. With the exception of the Han River basin, the regression analysis and Mann-Kendall and Sen results failed to detect trends for the runoff and rainfall over the study period. Rapid land use changes were linked to the increase in the runoff in the Han River basin. The sensitivity of the evapotranspiration and ultimately the runoff to the meteorological variables was in the order of relative humidity > sunshine duration > wind speed > $T_{max}$ > $T_{min}$. Future studies should investigate the interaction of the variables analyzed herein, and their relative contributions to the runoff trends.

The Impact of Institutional Quality on FDI Inflows: The Evidence from Capital Outflow of Asian Economies

  • LE, Anh Hoang;KIM, Taegi
    • The Journal of Asian Finance, Economics and Business
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    • 제8권8호
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    • pp.335-343
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    • 2021
  • This paper investigates the effect of institutional quality on FDI inflows by using FDI outflows from Asian countries from 2009 to 2017. We used the FDI data from five major Asian economies, which are South Korea, China, Japan, Singapore, and Hong Kong. The gravity model was used to examine the effect of institutional quality on FDI flows. The regression model considers several independent variables, and we select the most appropriate variables by using the Bayesian Model Averaging (BMA) estimator. We have shown that foreign direct investment from Asian countries depends on the size of home and the partner countries, geographical distance, trade interaction between two countries, economic freedom, labor supply, tariff rate, and capacity of the government. The results of different estimation techniques emphasize that multinational enterprises prefer to invest in those countries which have a higher income, which shows the evidence for Lucas's paradox. The results also show that economic freedom and control of corruption have a positive impact on FDI inwards. The regression results show that better institutional quality in host countries encourages more FDIs from Asian economies. It suggests that the state should control corruption and create a free economic environment to attract FDIs.

An Efficient Algorithm to Develop Model for Predicting Bead Width in Butt Welding

  • Kim, I.S.;Son, J.S.
    • International Journal of Korean Welding Society
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    • 제1권2호
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    • pp.12-17
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    • 2001
  • With the advance of the robotic welding process, procedure optimization that selects the welding procedure and predicts bead width that will be deposited is increased. A major concern involving procedure optimization should define a welding procedure that can be shown to be the best with respect to some standard and chosen combination of process parameters, which give an acceptable balance between production rate and the scope of defects for a given situation. This paper presents a new algorithm to establish a mathematical model f3r predicting bead width through a neural network and multiple regression methods, to understand relationships between process parameters and bead width, and to predict process parameters on bead width for GMA welding process. Using a series of robotic arc welding, additional multi-pass butt welds were carried out in order to verify the performance of the neural network estimator and multiple regression methods as well as to select the most suitable model. The results show that not only the proposed models can predict the bead width with reasonable accuracy and guarantee the uniform weld quality, but also a neural network model could be better than the empirical models.

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윷의 확률 추정에 대하여 (On estimation of the probability of Yut)

  • 박진경;박승선
    • 응용통계연구
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    • 제9권2호
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    • pp.83-94
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    • 1996
  • 윷의 확률에 대한 기하학적 접근의 선행연구가 있었고, 이 논문은 그 선행연구를 보완, 발전시키는데 목적을 두고 있다. 특히, 윷의 확률이 '논리적'으로 계산되기 어려운 상황과 그 이유를 설명하고, 통계학적인 추정방법들을 제시하고 있다. 시중에 판매되고 있는 여러가지 종류의 윷을 사용함으로써 실질적인 회귀선을 유도하였고, 이와 같이 추정된 확률을 통하여 도, 개, 걸, 윷, 모의 출현빈도순서 및 예상확률을 구할 수 있게 되었다. 이러한 통계학적인 접근의 결과는 기초확률시간이나 기초통계학 시간에 활용될 수 있을 것이다.

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A Comparision on CERES & Robust-CERES

  • 오광식;도수희;김대학
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2003년도 추계학술대회
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    • pp.93-100
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    • 2003
  • It is necessary to check the curvature of selected covariates in regression diagnostics. There are various graphical methods using residual plots based on least squares fitting. The sensitivity of LS fitting to outliers can distort their residuals, making the identification of the unknown function difficult to impossible. In this paper, we compare combining conditional expectation and residual plots(CERES Plots) between least square fit and robust fits using Huber M-estimator. Robust CERES will be far less distorted than their LS counterparts in the presence of outliers and hence, will be more useful in identifying the unknown function.

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Applicability of the Ordinary Least Squares Procedure When Both Variables are Subject to Error

  • Kim, Kil-Soo;Byun, Jai-Hyun;Yum, Bong-Jin
    • 한국경영과학회지
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    • 제21권1호
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    • pp.163-170
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    • 1996
  • An errors-in-variables model (EVM) differs from the classical regression model in that in the former the independent variable is also subject to error. This paper shows that to assess the applicability of the ordinary least squares (OLS) estimation procedure to the EVM, the relative dispersion of the independent variable to its error variance must be also considered in addition to Mandel's criterion. The effect of physically reducing the variance of errors in the independent variable on the performance of the OLS slope estimator is also discussed.

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스트랩다운 적외선 영상센서를 위한 관성센서 기반 강인최소자승 움직임 훼손영상 복원 기법 (Robust Least Squares Motion Deblurring Using Inertial Sensor for Strapdown Image IR Sensors)

  • 김기승;나성웅
    • 제어로봇시스템학회논문지
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    • 제18권4호
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    • pp.314-320
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    • 2012
  • This paper proposes a new robust motion deblurring filter using the inertial sensor measurements for strapdown image IR applications. With taking the PSF measurement error into account, the motion blurred image is modeled by the linear uncertain state space equation with the noise corrupted measurement matrix and the stochastic parameter uncertainty. This motivates us to solve the motion deblurring problem based on the recently developed robust least squares estimation theory. In order to suppress the ringing effect on the deblurred image, the robust least squares estimator is slightly modified by adoping the ridge-regression concept. Through the computer simulations using the actual IR scenes, it is demonstrated that the proposed algorithm shows superior and reliable motion deblurring performance even in the presence of time-varying motion artifact.

국내·외 계기지진 정보를 활용한 중·약진 지역의 스펙트럴 가속도 응답 예측식 (Prediction Equation of Spectral Acceleration Responses in Low-to-Moderate Seismic Regions using Domestic and Overseas Earthquake Records)

  • 신동현;김형준
    • 한국지진공학회논문집
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    • 제22권2호
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    • pp.77-86
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    • 2018
  • This study develops an empirical prediction equation of spectral acceleration responses of earthquakes which can induce structural damages. Ground motion records representing hazards of low-to-moderate seismic regions were selected and organized with several influential factors affecting the response spectra. The empirical equation and estimator coefficients for acceleration response spectra were then proposed using a robust nonlinear optimization coupled with a regression analysis. For analytical verification of the prediction equation, response spectra used for low-to-moderate seismic regions were estimated and the predicted results were comparatively evaluated with measured response spectra. As a result, the predicted shapes of response spectra can simulate the graphical shapes of measured data with high accuracy and most of predicted results are distributed inside range of correlation of variation (COV) of 30% from perfectly correlated lines.

신경회로망을 이용한 비드폭 예측 (Prediction of the Bead Width Using an Artificial Neural Network)

  • 김일수;손준식;박창언;하용훈;성백섭
    • Journal of Welding and Joining
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    • 제18권4호
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    • pp.48-54
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    • 2000
  • Adaptive control in the robotic GMA(Gas Metal Arc) welding is employed to monitor information about weld characteristics and process parameters as well; as t modify those parameters to hold weld. The objectives of this paper are to realize the mapping characteristics of bead width through the neural network and multiple regression method as well as to select the most accurate model in order to control the weld quality(bead width0. The experimental results show that the proposed neural network estimator can predict bead width with reasonable accuracy, and guarantee the uniform weld quality.

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