• Title/Summary/Keyword: Multiple linear Regression

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Detection of Change-Points by Local Linear Regression Fit;

  • Kim, Jong Tae;Choi, Hyemi;Huh, Jib
    • Communications for Statistical Applications and Methods
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    • v.10 no.1
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    • pp.31-38
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    • 2003
  • A simple method is proposed to detect the number of change points and test the location and size of multiple change points with jump discontinuities in an otherwise smooth regression model. The proposed estimators are based on a local linear regression fit by the comparison of left and right one-side kernel smoother. Our proposed methodology is explained and applied to real data and simulated data.

Estimation of AADT Using Multiple Linear Regression in Isolated Area (다중선형 회귀분석을 이용한 고립지역에서의 AADT 추정방안 연구)

  • Kim, Tae-woon;Oh, Ju-sam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.35 no.4
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    • pp.887-896
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    • 2015
  • This study estimates future AADT using historical AADT and socio-economic factors in isolated area. Multiple linear regression method by socio-economic factors are lower MAPE and higher R-square than using historical AADT. Analysis of socio-economic factors influence AADT in isolated typical areas, varied socio-economic factors influence on AADT. In isolated coastal areas, oil price influence on AADT. AADT forecasting model in isolated area is excellent when analysising $R^2$ and MAPE. It is assume that estimation of AADT in isolated area using multiple linear regression is accurate because of a little passed traffic volume and traffic volume fluctuation.

Comparison of Data-based Real-Time Flood Forecasting Model (자료기반 실시간 홍수예측 모형의 비교·검토)

  • Choi, Hyun Gu;Han, Kun Yeun;Roh, Hong Sik;Park, Se Jin
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.5
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    • pp.1809-1827
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    • 2013
  • Recently we need to take various measures to prepare for extreme flood that occur due to climate change. It is important that establish flood forecasting system to prepare flood over non-structure measures. The objective of this study is to develop superior real-time flood forecasting model by comparing the Neuro-fuzzy model and the multiple linear regression model. The Neuro-fuzzy model and the multiple linear regression model are established using same input data and applied for various flood events in Nakdong basin. The results show that the Neuro-fuzzy model can carry out flood forecasting results more accurately than the multiple linear regression model. This study can contribute to the establishment of a high accuracy flood information system that secure lead time in Nakdong basin.

Evaluation of applicability of pan coefficient estimation method by multiple linear regression analysis (다변량 선형회귀분석을 이용한 증발접시계수 산정방법 적용성 검토)

  • Rim, Chang-Soo
    • Journal of Korea Water Resources Association
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    • v.55 no.3
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    • pp.229-243
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    • 2022
  • The effects of monthly meteorological data measured at 11 stations in South Korea on pan coefficient were analyzed to develop the four types of multiple linear regression models for estimating pan coefficients. To evaluate the applicability of developed models, the models were compared with six previous models. Pan coefficients were most affected by air temperature for January, February, March, July, November and December, and by solar radiation for other months. On the whole, for 12 months of the year, the effects of wind speed and relative humidity on pan coefficient were less significant, compared with those of air temperature and solar radiation. For all meteorological stations and months, the model developed by applying 5 independent variables (wind speed, relative humidity, air temperature, ratio of sunshine duration and daylight duration, and solar radiation) for each station was the most effective for evaporation estimation. The model validation results indicate that the multiple linear regression models can be applied to some particular stations and months.

Estimation of HCHO Column Using a Multiple Regression Method with OMI and MODIS Data

  • Hong, Hyunkee;Yang, Jiwon;Kang, Hyeongwoo;Kim, Daewon;Lee, Hanlim
    • Korean Journal of Remote Sensing
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    • v.35 no.4
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    • pp.503-516
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    • 2019
  • We have estimated the vertical column density (VCD) of formaldehyde (HCHO) on a global scale using a multiple linear regression method (MRM) with Ozone Monitoring Instrument (OMI) and Moderate-Resolution Imaging Spectroradiometer (MODIS) data. HCHO VCDs were estimated in regions of biogenic, pyrogenic, and anthropogenic emissions using independent variables, including $NO_2$ VCD, land surface temperature (LST), an enhanced vegetation index (EVI), and the mean fire radiative power (MFRP), which are strongly correlated with HCHO. To evaluate the HCHO estimates obtained using the MRM, we compared estimates of HCHO VCD data measured by OMI ($HCHO_{OMI}$) with those estimated by multiple linear regression equations (MRE) ($HCHO_{MRE}$). Good MRM performances were found, having the average statistical values (R = 0.91, slope = 1.03, mean bias = $-0.12{\times}10^{15}molecules\;cm^{-2}$, percent difference = 11.27%) between $HCHO_{MRE}$ and $HCHO_{OMI}$ in our study regions where high HCHO levels are present. Our results demonstrate that the MRM can be a useful tool for estimating atmospheric HCHO levels.

유전자 알고리듬을 이용한 다중이상치 탐색

  • Go Yeong-Hyeon;Lee Hye-Seon;Jeon Chi-Hyeok
    • Proceedings of the Korean Statistical Society Conference
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    • 2000.11a
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    • pp.173-179
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    • 2000
  • Genetic algorithm(GA) is applied for detecting multiple outliers. GA is a heuristic optimization tool solving for near optimal solution. We compare the performance of GA and the other diagnostic measures commonly used for detecting outliers in regression model. The results show that GA seems to have better performance than the others for the detection of multiple outliers.

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A Study on the Weight Estimation Model of Floating Offshore Structures using the Non-linear Regression Analysis (비선형 회귀 분석을 이용한 부유식 해양 구조물의 중량 추정 모델 연구)

  • Seo, Seong-Ho;Roh, Myung-Il;Shin, Hyunkyoung
    • Journal of the Society of Naval Architects of Korea
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    • v.51 no.6
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    • pp.530-538
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    • 2014
  • The weight estimation of floating offshore structures such as FPSO, TLP, semi-Submersibles, Floating Offshore Wind Turbines etc. in the preliminary design, is one of important measures of both construction cost and basic performance. Through both literature investigation and internet search, the weight data of floating offshore structures such as FPSO and TLP was collected. In this study, the weight estimation model was suggested for FPSO. The weight estimation model using non-linear regression analysis was established by fixing independent variables based on this data and the multiple regression analysis was introduced into the weight estimation model. Its reliability was within 4% of error rate.

Relation between the Building Exterior Conditions and Energy Costs in the Running period of the Apartment Housing (공동주택의 건물외부조건과 에너지비용과의 관계분석)

  • Lee, Kang-Hee;Ryu, Seung-Hoon;Lee, Yeun-Taek
    • KIEAE Journal
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    • v.9 no.1
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    • pp.107-113
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    • 2009
  • The energy cost is resulted from the energy use. Its sources are divided into some types and depended on the building use or energy-use type. The energy cost should be affected by the amount of the energy use. The cost could be calculated to consider various factors such as the insulation, heating type, building shape and others. But it can not consider all of the affect factors to the energy cost and need to categorize the factors to the condition for estimating the cost. In this paper, it aimed at providing the estimation model in linear equation and multiple linear regression, utilizing the building exterior condition and management characteristics in apartment housing. Its survey are conducted in two parts of management characteristics and building exterior condition. The correlation analysis is conducted to get rid of the multicolinearity among the inputted factors. The number of linear equation model is 11 and includes the 1st, 2nd and 3rd equation function, power function and others. Among these, it suggested the 2nd and 3rd function and power function in terms of the statistics. In multiple linear regression model, the building volume and management area are inputted to the estimation.

Reliability Improvement of In-Place Concreter Strength Prediction by Ultrasonic Pulse Velocity Method (초음파 속도법에 의한 현장 콘크리트 강도추정의 신뢰성 향상)

  • 원종필;박성기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.43 no.4
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    • pp.97-105
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    • 2001
  • The ultrasonic pulse velocity test has a strong potential to be developed into a very useful and relatively inexpensive in-place test for assuring the quality of concrete placed in structure. The main problem in realizing this potential is that the relationship between compressive strength ad ultrasonic pulse velocity is uncertain and concrete is an inherently variable material. The objective of this study is to improve the reliability of in-place concrete strength predictions by ultrasonic pulse velocity method. Experimental cement content, s/a rate, and curing condition of concrete. Accuracy of the prediction expressed in empirical formula are examined by multiple regression analysis and linear regression analysis and practical equation for estimation the concrete strength are proposed. Multiple regression model uses water-cement ratio cement content s/a rate, and pulse velocity as dependent variables and the compressive strength as an independent variable. Also linear regression model is used to only pulse velocity as dependent variables. Comparing the results of the analysis the proposed equation expressed highest reliability than other previous proposed equations.

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N-supplying Capability Evaluation of Corn Field Soils in Pennsylvania (Pennsylvania주 옥수수 재배 토양의 질소공급능력 평가)

  • Hong, Soon-Dal
    • Korean Journal of Soil Science and Fertilizer
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    • v.31 no.4
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    • pp.359-367
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    • 1998
  • In order to determine the nitrogen supplying capabilities (NSC) of corn fields, 47 field experiments were performed in Pennsylvania over 3 year from 1986 and NSCs were estimated by the regression analysis with chemical properties and soil attributes. Although the content of $NO_3-N$ in soil showed the best correlation with NSC ($R^2=0.518$), the standardized partial regression coefficient of $NO_3-N$ for NSC was 0.52, with some variations over the years. This value was slightly higher than those of the other properties which ranged from 0.001 to 0.351. Multiple linear regression with soil attributes for the evaluation of NSC was better than simple regression with $NO_3-N$. The coefficient of determination ($R^2$) for the evaluation of NSC was gradually increased; 0.599 with selected chemical properties, 0.698 with quantitative attributes(chemical properties and depth of Ap horizon), and 0.839 with quantitative and selected qualitative soil attributes. Consequently, in order to evaluate NSC, analysis by multiple linear regression with soil attributes was more reliable and better model than by the simple regression model.

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