• 제목/요약/키워드: Exponential smoothing methods

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Exponential Smoothing with an Adaptive Response to Random Level Changes (임의의 수준변화에 적절히 반응할 수 있는 지수이동가중평균법)

  • Jun, Duk-Bin
    • Journal of Korean Institute of Industrial Engineers
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    • v.16 no.2
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    • pp.129-134
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    • 1990
  • Exponential smoothing methods have enjoyed a long history of successful applications and have been used in forecasting for many years. However, it has been long known that one of the deficiencies of the method is an inability to respond quickly to interventions to interruptions, or to large changes in level of the underlying process. An exponential smoothing method adaptive to repeated random level changes is proposed using a change-detection statistic derived from a simple dynamic linear model. The results are compared with Trigg and Leach's and the exponential smoothing methods.

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Estimation of Smoothing Constant of Minimum Variance and its Application to Industrial Data

  • Takeyasu, Kazuhiro;Nagao, Kazuko
    • Industrial Engineering and Management Systems
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    • v.7 no.1
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    • pp.44-50
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    • 2008
  • Focusing on the exponential smoothing method equivalent to (1, 1) order ARMA model equation, a new method of estimating smoothing constant using exponential smoothing method is proposed. This study goes beyond the usual method of arbitrarily selecting a smoothing constant. First, an estimation of the ARMA model parameter was made and then, the smoothing constants. The empirical example shows that the theoretical solution satisfies minimum variance of forecasting error. The new method was also applied to the stock market price of electrical machinery industry (6 major companies in Japan) and forecasting was accomplished. Comparing the results of the two methods, the new method appears to be better than the ARIMA model. The result of the new method is apparently good in 4 company data and is nearly the same in 2 company data. The example provided shows that the new method is much simpler to handle than ARIMA model. Therefore, the proposed method would be better in these general cases. The effectiveness of this method should be examined in various cases.

Robust Method of Video Contrast Enhancement for Sudden Illumination Changes (급격한 조명 변화에 강건한 동영상 대조비 개선 방법)

  • Park, Jin Wook;Moon, Young Shik
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.11
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    • pp.55-65
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    • 2015
  • Contrast enhancement methods for a single image applied to videos may cause flickering artifacts because these methods do not consider continuity of videos. On the other hands, methods considering the continuity of videos can reduce flickering artifacts but it may cause unnecessary fade-in/out artifacts when the intensity of videos changes abruptly. In this paper, we propose a robust method of video contrast enhancement for sudden illumination changes. The proposed method enhances each frame by Fast Gray-Level Grouping(FGLG) and considers the continuity of videos by an exponential smoothing filter. The proposed method calculates the smoothing factor of an exponential smoothing filter using a sigmoid function and applies to each frame to reduce unnecessary fade-in/out effects. In the experiment, 6 measurements are used for the performance analysis of the proposed method and traditional methods. Through the experiment. it has been shown that the proposed method demonstrates the best quantitative performance of MSSIM and Flickering score and show the adaptive enhancement under sudden illumination change through the visual quality comparison.

Computation and Smoothing Parameter Selection In Penalized Likelihood Regression

  • Kim Young-Ju
    • Communications for Statistical Applications and Methods
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    • v.12 no.3
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    • pp.743-758
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    • 2005
  • This paper consider penalized likelihood regression with data from exponential family. The fast computation method applied to Gaussian data(Kim and Gu, 2004) is extended to non Gaussian data through asymptotically efficient low dimensional approximations and corresponding algorithm is proposed. Also smoothing parameter selection is explored for various exponential families, which extends the existing cross validation method of Xiang and Wahba evaluated only with Bernoulli data.

An Empirical Study on Supply Chain Demand Forecasting Using Adaptive Exponential Smoothing (적응적 지수평활법을 이용한 공급망 수요예측의 실증분석)

  • Kim, Jung-Il;Cha, Kyoung-Cheon;Jun, Duk-Bin;Park, Dae- Keun;Park, Sung-Ho;Park, Myoung-Whan
    • IE interfaces
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    • v.18 no.3
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    • pp.343-349
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    • 2005
  • This study presents the empirical results of comparing several demand forecasting methods for Supply Chain Management(SCM). Adaptive exponential smoothing using change detection statistics (Jun) is compared with Trigg and Leach's adaptive methods and SAS time series forecasting systems using weekly SCM demand data. The results show that Jun's method is superior to others in terms of one-step-ahead forecast error and eight-step-ahead forecast error. Based on the results, we conclude that the forecasting performance of SCM solution can be improved by the proposed adaptive forecasting method.

A Study on the Prediction of Power Demand for Electric Vehicles Using Exponential Smoothing Techniques (Exponential Smoothing기법을 이용한 전기자동차 전력 수요량 예측에 관한 연구)

  • Lee, Byung-Hyun;Jung, Se-Jin;Kim, Byung-Sik
    • Journal of Korean Society of Disaster and Security
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    • v.14 no.2
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    • pp.35-42
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    • 2021
  • In order to produce electric vehicle demand forecasting information, which is an important element of the plan to expand charging facilities for electric vehicles, a model for predicting electric vehicle demand was proposed using Exponential Smoothing. In order to establish input data for the model, the monthly power demand of cities and counties was applied as independent variables, monthly electric vehicle charging stations, monthly electric vehicle charging stations, and monthly electric vehicle registration data. To verify the accuracy of the electric vehicle power demand prediction model, we compare the results of the statistical methods Exponential Smoothing (ETS) and ARIMA models with error rates of 12% and 21%, confirming that the ETS presented in this paper is 9% more accurate as electric vehicle power demand prediction models. It is expected that it will be used in terms of operation and management from planning to install charging stations for electric vehicles using this model in the future.

Multivariate exponential smoothing models with application to exchange rates (다변량 지수평활모형을 이용한 환율 분석)

  • Lee, Yeonha;Seong, Byeongchan
    • The Korean Journal of Applied Statistics
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    • v.33 no.3
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    • pp.257-267
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    • 2020
  • We introduce multivariate exponential smoothing models based on a vector innovations structural time series framework. The models enable us to exploit potential inter-series dependencies to improve the fit and forecasts of multivariate (vector) time series. Models are applied to forecast the exchange rates of the UK pound (UKP) and US dollar (USD) against the Korean won (KRW) observed on monthly basis; subseqently, we compare their performance with alternative models. We observe that the multivariate exponential smoothing models are superior to alternatives.

Optimal Coefficient Selection of Exponential Smoothing Model in Short Term Load Forecasting on Weekdays (평일 단기전력수요 예측을 위한 최적의 지수평활화 모델 계수 선정)

  • Song, Kyung-Bin;Kwon, Oh-Sung;Park, Jeong-Do
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.2
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    • pp.149-154
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    • 2013
  • Short term load forecasting for electric power demand is essential for stable power system operation and efficient power market operation. High accuracy of the short term load forecasting can keep the power system more stable and save the power market operation cost. We propose an optimal coefficient selection method for exponential smoothing model in short term load forecasting on weekdays. In order to find the optimal coefficient of exponential smoothing model, load forecasting errors are minimized for actual electric load demand data of last three years. The proposed method are verified by case studies for last three years from 2009 to 2011. The results of case studies show that the average percentage errors of the proposed load forecasting method are improved comparing with errors of the previous methods.

A Study on the Prediction of the World Seaborne Trade Volume through the Exponential Smoothing Method and Seemingly Unrelated Regression Model (지수평활법과 SUR 모형을 통한 세계 해상물동량 예측 연구)

  • Ahn, Young-Gyun
    • Korea Trade Review
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    • v.44 no.2
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    • pp.51-62
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    • 2019
  • This study predicts the future world seaborne trade volume with econometrics methods using 23-year time series data provided by Clarksons. For this purpose, this study uses simple regression analysis, exponential smoothing method and seemingly unrelated regression model (SUR Model). This study is meaningful in that it predicts worldwide total seaborne trade volume and seaborne traffic in four major items (container, bulk, crude oil, and LNG) from 2019 to 2023 as there are few prior studies that predict future seaborne traffic using recent data. It is expected that more useful references can be provided to trade related workers if the analysis period was increased and additional variables could be included in future studies.

A comparative analysis of the Demand Forecasting Models : A case study (수요예측 모형의 비교분석에 관한 사례연구)

  • Jung, Sang-Yoon;Hwang, Gye-Yeon;Kim, Yong-Jin;Kim, Jin
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.17 no.31
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    • pp.1-10
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    • 1994
  • The purpose of this study is to search for the most effective forecasting model for condenser with independent demand among the quantitative methods such as Brown's exponential smoothing method, Box-Jenkins method, and multiple regression analysis method. The criterion for the comparison of the above models is mean squared error(MSE). The fitting results of these three methods are as follows. 1) Brown's exponential smoothing method is the simplest one, which means the method is easy to understand compared to others. But the precision is inferior to other ones. 2) Box-Jenkins method requires much historic data and takes time to get to the final model, although the precision is superior to that of Brown's exponential smoothing method. 3) Regression method explains the correlation between parts with similiar demand pattern, and the precision is the best out of three methods. Therefore, it is suggested that the multiple regression method is fairly good in precision for forecasting our item and that the method is easily applicable to practice.

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