• Title/Summary/Keyword: Error Term

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An Empirical Analysis on the Long-term Balance of Bunker Oil Prices Using the Co-integration Model and Vector Error Correction Model (공적분·벡터오차수정모형을 활용한 벙커유 가격의 장기균형 수렴에 관한 실증분석)

  • Ahn, Young-Gyun;Lee, Min-Kyu
    • Korea Trade Review
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    • v.44 no.1
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    • pp.75-86
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    • 2019
  • This study performs a factor analysis that affects the bunker oil price using the Co-integration model and Vector Error Correction Model (VECM). For this purpose, we use data from Clarkson and the analysis results show 17.6% decrease in bunker oil price when the amount of crude oil production increases at 1.0%, 10.3% increase in bunker oil price when the seaborne trade volume increases at 1.0%, 1.0% decrease in bunker oil price when total volume of vessels increases at 1.0%, and 0.003% increase in bunker oil price when 1.0% increase in world GDP, respectively. This study is meaningful in that this study estimates the speed of convergence to long-term equilibrium and identifies the price adjust mechanism which naturally exists in bunker oil market. And it is expected that the future study can provide statistically more meaningful econometric results if it can obtain data during more long-periods and use more various kinds of explanatory variables.

A Novel Second Order Radial Basis Function Neural Network Technique for Enhanced Load Forecasting of Photovoltaic Power Systems

  • Farhat, Arwa Ben;Chandel, Shyam.Singh;Woo, Wai Lok;Adnene, Cherif
    • International Journal of Computer Science & Network Security
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    • v.21 no.2
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    • pp.77-87
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    • 2021
  • In this study, a novel improved second order Radial Basis Function Neural Network based method with excellent scheduling capabilities is used for the dynamic prediction of short and long-term energy required applications. The effectiveness and the reliability of the algorithm are evaluated using training operations with New England-ISO database. The dynamic prediction algorithm is implemented in Matlab and the computation of mean absolute error and mean absolute percent error, and training time for the forecasted load, are determined. The results show the impact of temperature and other input parameters on the accuracy of solar Photovoltaic load forecasting. The mean absolute percent error is found to be between 1% to 3% and the training time is evaluated from 3s to 10s. The results are also compared with the previous studies, which show that this new method predicts short and long-term load better than sigmoidal neural network and bagged regression trees. The forecasted energy is found to be the nearest to the correct values as given by England ISO database, which shows that the method can be used reliably for short and long-term load forecasting of any electrical system.

Linear Measurement Error Variance Estimation based on the Complex Sample Survey Data

  • Heo, Sunyeong;Chang, Duk-Joon
    • Journal of Integrative Natural Science
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    • v.5 no.3
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    • pp.157-162
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    • 2012
  • Measurement error is one of main source of error in survey. It is generally defined as the difference between an observed value and an underlying true value. An observed value with error may be expressed as a function of the true value plus error term. In some cases, the measurement error variance may be also a function of the unknown true value. The error variance function can be rewritten as a function of true value multiplied by a scale factor. This research explore methods for estimation of the measurement error variance based on the data from complex sampling design. We consider the case in which the variance of mesurement error is a linear function of unknown true value, and the error variance scale factor is small. We applied our results to the U.S. Third National Health and Nutrition Examination Survey (the U.S. NHANES III) data for empirical analyses, which has replicate measurements for relatively small subset of initial respondents's group.

The Relationship between World Oil Price and Consummer Price Index in Korea (국제유가와 소비자물가의 변동)

  • Kim, Youngduk
    • Environmental and Resource Economics Review
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    • v.9 no.2
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    • pp.373-391
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    • 2000
  • This paper investigates the existence of a long-run relationship between world oil price and consumer price index for Korea during 1983~1999. The cointegration and error correction modelling approaches have been applied. Empirical results suggest that there exists a long-run relationship among world oil prices. consumer prices, M2 and a production gap variable. The dynamic behavior of the relationship has been investigated by estimating a error correction model, in which the error correction term have been found significant. The error correction model has also been found to be robust as it satisfy almost all relevant diagnostic tests.

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A Study on the Comparison of Electricity Forecasting Models: Korea and China

  • Zheng, Xueyan;Kim, Sahm
    • Communications for Statistical Applications and Methods
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    • v.22 no.6
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    • pp.675-683
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    • 2015
  • In the 21st century, we now face the serious problems of the enormous consumption of the energy resources. Depending on the power consumption increases, both China and South Korea face a reduction in available resources. This paper considers the regression models and time-series models to compare the performance of the forecasting accuracy based on Mean Absolute Percentage Error (MAPE) in order to forecast the electricity demand accurately on the short-term period (68 months) data in Northeast China and find the relationship with Korea. Among the models the support vector regression (SVR) model shows superior performance than time-series models for the short-term period data and the time-series models show similar results with the SVR model when we use long-term period data.

A GAUSSIAN WHITE NOISE GENERATOR AND ITS APPLICATION TO THE FLUCTUATION-DISSIPATION FORMULA

  • Moon, Byung-Soo
    • Journal of applied mathematics & informatics
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    • v.15 no.1_2
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    • pp.363-375
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    • 2004
  • In this paper, We show that the bandpass random signals of the form ∑$_{\alpha}$$\alpha$$_{\alpha}$ a Sin(2$\pi$f$_{\alpha}$t + b$_{\alpha}$) where a$_{\alpha}$ being a random number in [0,1], f$_{\alpha}$ a random integer in a given frequency band, and b$_{\alpha}$ a random number in [0, 2$\pi$], generate Gaussian white noise signals and hence they are adequate for simulating Continuous Markov processes. We apply the result to the fluctuation-dissipation formula for the Johnson noise and show that the probability distribution for the long term average of the power of the Johnson noise is a X$^2$ distribution and that the relative error of the long term average is (equation omitted) where N is the number of blocks used in the average.error of the long term average is (equation omitted) where N is the number of blocks used in the average.

A Study on the Term of Warranty Liability by the Law-suit Requesting of the Guarantee against Defects in the Apartment Building (공동주택 하자보증금 청구소송에 의한 하자담보책임기간 연구)

  • Koo, Hae-Shik
    • KIEAE Journal
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    • v.12 no.3
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    • pp.11-18
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    • 2012
  • The purpose of this study is to contribute to solution of the defect dispute in apartment house in advance. We want to propose the improved devices in defect problems by investigating the money that exacted from the practical business of the inspection company and the money that a judge gave a decision in a civil court in 50 cases of the lawsuit to requesting the guarantee against defects and the improved schemes of the applied rate by analyzing the diagnosis money of each applied years about the term of warranty liability in 40 cases of the lawsuit separately from that. As the result, we have to reflect the defect of non construction and error construction on apartment building defects, which recognizes very important factor when we compute the defect repair warranty money and it needs to be rearranged the applied ratio in guarantee peried of housing law practically.

An Efficient Algorithm for Performance Analysis of Multi-cell and Multi-user Wireless Communication Systems

  • Wang, Aihua;Lu, Jihua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.11
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    • pp.2035-2051
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    • 2011
  • Theoretical Bit Error Rate (BER) and channel capacity analysis are always of great interest to the designers of wireless communication systems. At the center of such analyses people are often encountered with a high-dimensional multiple integrals with quite complex integrands. Conventional Gaussian quadrature is inefficient in handling problems like this, as it tends to entail tremendous computational overhead, and the principal order of its error term increase rapidly with the dimension of the integral. In this paper, we propose a new approach to calculate complex multi-fold integrals based on the number theory. In contrast to Gaussian quadrature, the proposed approach requires less computational effort, and the principal order of its error term is independent of the dimension. The effectiveness of the number theory based approach is examined in BER and capacity analyses for practical systems. In particular, the results generated by numerical computation turn out in good match with that of Monte-Carlo simulations.

Error Free Butcher Algorithms for Linear Electrical Circuits

  • Murugesan, K.;Gopalan, N.P.;Gopal, Devarajan
    • ETRI Journal
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    • v.27 no.2
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    • pp.195-205
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    • 2005
  • In this paper, an error-free Butcher algorithm is introduced to study the singular system of a linear electrical circuit for time invariant and time varying cases. The discrete solutions obtained using Runge-Kutta (RK)-Butcher algorithms are compared with the exact solutions of the electrical circuit problem and are found to be very accurate. Stability regions for the single term Walsh series (STWS) method and the RK-Butcher algorithm are presented. Error graphs for inductor currents and capacitor voltages are presented in a graphical form to show the efficiency of the RK-Butcher algorithm. This RK-Butcher algorithm can be easily implemented in a digital computer for any singular system of electrical circuits.

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Measurement Delay Error Compensation for GPS/INS Integrated Systems

  • Lim, You-chol;Joon Lyou
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.33.1-33
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    • 2002
  • The INS provides high rate position, velocity and attitude data with good short-term stability while the GPS provides position and velocity data with long-term stability. By integrating the INS with GPS, a navigation system can be achieved to provide highly accurate navigation performance. For the best performance, time synchronization of GPS and INS data is very important in GPS/INS integrated system. But, it is impossible to synchronize them exactly due to the communication and computation time-delay. In this paper, to reduce the error caused by the measurement time-delay in GPS/INS integrated systems, error compensation methods using separate bias Kalman filter are suggested for both the...

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