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Prediction and driving factors of forest fire occurrence in Jilin Province,China
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作者 Bo Gao Yanlong Shan +4 位作者 Xiangyu Liu Sainan Yin Bo Yu Chenxi Cui Lili Cao 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期58-71,共14页
Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square kilometers.Prevention is better than suppression and prediction models of forest fire occurrence have dev... Forest fires are natural disasters that can occur suddenly and can be very damaging,burning thousands of square kilometers.Prevention is better than suppression and prediction models of forest fire occurrence have developed from the logistic regression model,the geographical weighted logistic regression model,the Lasso regression model,the random forest model,and the support vector machine model based on historical forest fire data from 2000 to 2019 in Jilin Province.The models,along with a distribution map are presented in this paper to provide a theoretical basis for forest fire management in this area.Existing studies show that the prediction accuracies of the two machine learning models are higher than those of the three generalized linear regression models.The accuracies of the random forest model,the support vector machine model,geographical weighted logistic regression model,the Lasso regression model,and logistic model were 88.7%,87.7%,86.0%,85.0%and 84.6%,respectively.Weather is the main factor affecting forest fires,while the impacts of topography factors,human and social-economic factors on fire occurrence were similar. 展开更多
关键词 Forest fire Occurrence prediction Forest fire driving factors Generalized linear regression models Machine learning models
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Development of a Quantitative Prediction Support System Using the Linear Regression Method
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作者 Jeremie Ndikumagenge Vercus Ntirandekura 《Journal of Applied Mathematics and Physics》 2023年第2期421-427,共7页
The development of prediction supports is a critical step in information systems engineering in this era defined by the knowledge economy, the hub of which is big data. Currently, the lack of a predictive model, wheth... The development of prediction supports is a critical step in information systems engineering in this era defined by the knowledge economy, the hub of which is big data. Currently, the lack of a predictive model, whether qualitative or quantitative, depending on a company’s areas of intervention can handicap or weaken its competitive capacities, endangering its survival. In terms of quantitative prediction, depending on the efficacy criteria, a variety of methods and/or tools are available. The multiple linear regression method is one of the methods used for this purpose. A linear regression model is a regression model of an explained variable on one or more explanatory variables in which the function that links the explanatory variables to the explained variable has linear parameters. The purpose of this work is to demonstrate how to use multiple linear regressions, which is one aspect of decisional mathematics. The use of multiple linear regressions on random data, which can be replaced by real data collected by or from organizations, provides decision makers with reliable data knowledge. As a result, machine learning methods can provide decision makers with relevant and trustworthy data. The main goal of this article is therefore to define the objective function on which the influencing factors for its optimization will be defined using the linear regression method. 展开更多
关键词 prediction linear Regression Machine Learning Least Squares Method
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Tunnelling performance prediction of cantilever boring machine in sedimentary hard-rock tunnel using deep belief network 被引量:2
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作者 SONG Zhan-ping CHENG Yun +1 位作者 ZHANG Ze-kun YANG Teng-tian 《Journal of Mountain Science》 SCIE CSCD 2023年第7期2029-2040,共12页
Evaluating the adaptability of cantilever boring machine(CBM) through in-depth excavation and analysis of tunnel excavation data and rock mass parameters is the premise of mechanical design and efficient excavation in... Evaluating the adaptability of cantilever boring machine(CBM) through in-depth excavation and analysis of tunnel excavation data and rock mass parameters is the premise of mechanical design and efficient excavation in the field of underground space engineering.This paper presented a case study of tunnelling performance prediction method of CBM in sedimentary hard-rock tunnel of Karst landform type by using tunneling data and surrounding rock parameters.The uniaxial compressive strength(UCS),rock integrity factor(Kv),basic quality index([BQ]),rock quality index RQD,brazilian tensile strength(BTS) and brittleness index(BI) were introduced to construct a performance prediction database based on the hard-rock tunnel of Guiyang Metro Line 1 and Line 3,and then established the performance prediction model of cantilever boring machine.Then the deep belief network(DBN) was introduced into the performance prediction model,and the reliability of performance prediction model was verified by combining with engineering data.The study showed that the influence degree of surrounding rock parameters on the tunneling performance of the cantilever boring machine is UCS > [BQ] > BTS >RQD > Kv > BI.The performance prediction model shows that the instantaneous cutting rate(ICR) has a good correlation with the surrounding rock parameters,and the predicting model accuracy is related to the reliability of construction data.The prediction of limestone and dolomite sections of Line 3 based on the DBN performance prediction model shows that the measured ICR and predicted ICR is consistent and the built performance prediction model is reliable.The research results have theoretical reference significance for the applicability analysis and mechanical selection of cantilever boring machine for hard rock tunnel. 展开更多
关键词 Urban metro tunnel Cantilever boring machine Hard rock tunnel Performance prediction model linear regression Deep belief network
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The improved local linear prediction of chaotic time series 被引量:2
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作者 孟庆芳 彭玉华 孙佳 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3220-3225,共6页
Based on the Bayesian information criterion, this paper proposes the improved local linear prediction method to predict chaotic time series. This method uses spatial correlation and temporal correlation simultaneously... Based on the Bayesian information criterion, this paper proposes the improved local linear prediction method to predict chaotic time series. This method uses spatial correlation and temporal correlation simultaneously. Simulation results show that the improved local linear prediction method can effectively make multi-step and one-step prediction of chaotic time series and the multi-step prediction performance and one-step prediction accuracy of the improved local linear prediction method are superior to those of the traditional local linear prediction method. 展开更多
关键词 local linear prediction Bayesian information criterion state space reconstruction chaotic time series
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An adaptive strategy based on linear prediction of queue length to minimize congestion in Barabási-Albert scale-free networks 被引量:1
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作者 沈毅 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第5期632-636,共5页
In this paper, we propose an adaptive strategy based on the linear prediction of queue length to minimize congestion in Barabaisi-Albert (BA) scale-free networks. This strategy uses local knowledge of traffic condit... In this paper, we propose an adaptive strategy based on the linear prediction of queue length to minimize congestion in Barabaisi-Albert (BA) scale-free networks. This strategy uses local knowledge of traffic conditions and allows nodes to be able to self-coordinate their accepting probability to the incoming packets. We show that the strategy can delay remarkably the onset of congestion and systems avoiding the congestion can benefit from hierarchical organization of accepting rates of nodes. Furthermore, with the increase of prediction orders, we achieve larger values for the critical load together with a smooth transition from free-flow to congestion. 展开更多
关键词 linear prediction CONGESTION NETWORKS
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Multi-Level Inverter Linear Predictive Phase Composition Strategy for UPQC
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作者 M.Hari Prabhu K.Sundararaju 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2947-2958,共12页
The power system is facing numerous issues when the distributed gen-eration is added to the existing system.The existing power system has not been planned with flawless power quality control.These restrictions in the ... The power system is facing numerous issues when the distributed gen-eration is added to the existing system.The existing power system has not been planned with flawless power quality control.These restrictions in the power trans-mission generation system are compensated by the use of devices such as the Static Synchronous Compensator(STATCOM),the Unified Power Quality Con-ditioner(UPQC)series/shunt compensators,etc.In this work,UPQC’s plan with the joint activity of photovoltaic(PV)exhibits is proposed.The proposed system is made out of series and shunt regulators and PV.A boost converter connects the DC link to the PV source,allowing it to compensate for voltage sags,swells,vol-tage interferences,harmonics,and reactive power issues.In this paper,the fea-tures of a seven-level Cascaded H-Bridge Multi-Level idea are applied to shunt and series active filter changeovers to reduce Total Harmonic Distortion and com-pensate for voltage issues.Despite its power quality capacity for common cou-pling,the proposed system can inject the grid’s dynamic power.During voltage interference,it can also provide a piece of delicate burden power.The simulation is carried out with the help of MATLAB/SIMULINK programming,and the results are compared to those of other conventional methods. 展开更多
关键词 Unified power quality conditioner PHOTOVOLTAIC linear predictive phase composition total harmonic distortion
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Revisiting Akaike’s Final Prediction Error and the Generalized Cross Validation Criteria in Regression from the Same Perspective: From Least Squares to Ridge Regression and Smoothing Splines
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作者 Jean Raphael Ndzinga Mvondo Eugène-Patrice Ndong Nguéma 《Open Journal of Statistics》 2023年第5期694-716,共23页
In regression, despite being both aimed at estimating the Mean Squared Prediction Error (MSPE), Akaike’s Final Prediction Error (FPE) and the Generalized Cross Validation (GCV) selection criteria are usually derived ... In regression, despite being both aimed at estimating the Mean Squared Prediction Error (MSPE), Akaike’s Final Prediction Error (FPE) and the Generalized Cross Validation (GCV) selection criteria are usually derived from two quite different perspectives. Here, settling on the most commonly accepted definition of the MSPE as the expectation of the squared prediction error loss, we provide theoretical expressions for it, valid for any linear model (LM) fitter, be it under random or non random designs. Specializing these MSPE expressions for each of them, we are able to derive closed formulas of the MSPE for some of the most popular LM fitters: Ordinary Least Squares (OLS), with or without a full column rank design matrix;Ordinary and Generalized Ridge regression, the latter embedding smoothing splines fitting. For each of these LM fitters, we then deduce a computable estimate of the MSPE which turns out to coincide with Akaike’s FPE. Using a slight variation, we similarly get a class of MSPE estimates coinciding with the classical GCV formula for those same LM fitters. 展开更多
关键词 linear Model Mean Squared prediction Error Final prediction Error Generalized Cross Validation Least Squares Ridge Regression
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Prediction of Wind Speed Using a Hybrid Regression-Optimization Approach
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作者 Bhuvana Ramachandran Anbazhagan Swaminathan 《Journal of Power and Energy Engineering》 2023年第7期21-35,共15页
Predicting wind speed is a complex task that involves analyzing various meteorological factors such as temperature, humidity, atmospheric pressure, and topography. There are different approaches that can be used to pr... Predicting wind speed is a complex task that involves analyzing various meteorological factors such as temperature, humidity, atmospheric pressure, and topography. There are different approaches that can be used to predict wind speed, and a hybrid optimization approach is one of them. In this paper, the hybrid optimization approach combines a multiple linear regression approach with an optimization technique to achieve better results. In the context of wind speed prediction, this hybrid optimization approach can be used to improve the accuracy of existing prediction models. Here, a Grey Wolf Optimizer based Wind Speed Prediction (GWO-WSP) method is proposed. This approach is tested on the 2016, 2017, 2018, and 2019 Raw Data files from the Great Lakes Environmental Research Laboratories and the National Oceanic and Atmospheric Administration’s (GLERL-NOAA) Chicago Metadata Archive. The test results show that the implementation is successful and the approach yields accurate and feasible results. The computation time for execution of the algorithm is also superior compared to the existing methods in literature. 展开更多
关键词 Wind Speed prediction Multiple linear Regression Grey Wolf Optimizer Accuracy of Results Wind Power
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The Study of Contact Pressure Analyses and Prediction of Dynamic Fatigue Life for Linear Guideways System 被引量:1
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作者 Thin-Lin Horng 《Modern Mechanical Engineering》 2013年第2期69-76,共8页
The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center wi... The application of the linear guideways is very extensive, such as automation equipment, heavy-duty carry equipment, heavy-cut machining tool, CNC grinding machine, large-scale planning machine and machining center with the demand of high rigidity and heavy load. By means of the study of contact behavior between the roller/guideway and roller/slider, roller type linear guideways can improve the machining accuracy. The goal of this paper is to construct the fatigue life model of the linear guideway, with the help of the contact mechanics of rollers. In beginning, the analyses of the rigidity of a single roller compressed between guideway and slider was conducted. Then, the normal contact pressure of linear guideways was obtained by using the superposition method, and verified by the FEM software (ANSYS workbench). Finally, the bearing life theory proposed by Lundberg and Palmgren was used to describe the contact fatigue life. 展开更多
关键词 linear ROLLER Guideways SYSTEM Analysis SYSTEM Stress ANALYSES prediction of FATIGUE Life
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LINEAR PREDICTION APPROACH IN AIRBORNE ADAPTIVE ARRAYS
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作者 Su Jie Li Chunsheng Zhou Yinqing(Department of Electronic Engineering, Beijing University of Aeronautics and Astronautics, Beijing, China, 100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第1期64-70,共7页
To cope with the time-varying and Dopper-broadened clutter in airborne phase array radars, it is required that the signal processing should be adaptive and two-dimensional both in time and in space. However, the optim... To cope with the time-varying and Dopper-broadened clutter in airborne phase array radars, it is required that the signal processing should be adaptive and two-dimensional both in time and in space. However, the optimum two-dimensional adaptive processing is hard to realize real-timely because it requires a large amount of computation. From the idea of approximating the clutter process by using an auto regressive process, a linear prediction approach is proposed to realize the adaptive space-time processing of airborne adaptive array signals. The research shows that the clutter process can be well approximated by a low-order AR process, so a low-order linear prediction receiver can get a sub-optimum performance at a very low expense. Besides, the low-order linear prediction receiver has additional degrees of freedom to cope with other colored noises and interferences. In consideration of the many advantages of the linear prediction receiver in both algorithms and realizations, it has a good prospect in its application to air borne adaptive array signal processing. 展开更多
关键词 signal processing phased arrays RADAR linear prediction adaptive filters
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KLT-based local linear prediction of chaotic time series
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作者 Meng Qingfang Peng Yuhua Chen Yuehui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期694-699,共6页
In the reconstructed phase space, based on the Karhunen-Loeve transformation (KLT), the new local linear prediction method is proposed to predict chaotic time series. & noise-free chaotic time series and a noise ad... In the reconstructed phase space, based on the Karhunen-Loeve transformation (KLT), the new local linear prediction method is proposed to predict chaotic time series. & noise-free chaotic time series and a noise added chaotic time series are analyzed. The simulation results show that the KLT-based local linear prediction method can effectively make one-step and multi-step prediction for chaotic time series, and the one-step and multi-step prediction accuracies of the KLT-based local linear prediction method are superior to that of the traditional local linear prediction. 展开更多
关键词 Karhunen-Loeve transformation local linear prediction phase space reconstruction chaotic time series.
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Pyramid Linear Prediction Coding for Images
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作者 朱广进 赵风光 江峰 《Advances in Manufacturing》 SCIE CAS 1997年第2期155-158,共4页
Motivated by wavelet transform, this paper presents a pyramid linear prediction coding (PLPC) algorithmfor digitial images.The algorithm otltpots the rough colltour of an image and a prediction ermr sequence. In contr... Motivated by wavelet transform, this paper presents a pyramid linear prediction coding (PLPC) algorithmfor digitial images.The algorithm otltpots the rough colltour of an image and a prediction ermr sequence. In contrastto the conventional linear prediction method, PLPC exhibits very little sensitivity to channel ermrs and provides amore efficient compression performance. The results of simulations with Lena 512 X 512 and bitrates ranging from0.17 to 3.2 (lossless)bits/pixel are given to show that the PLPC method is very suitable for the human visualperception. 展开更多
关键词 linear prediction wavelet transform image compression
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ASP-Based Programs of Best Linear Unbiased Prediction-Estimated Breeding Values in Breeding Stock
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作者 FAN Qiang TIAN Chang-yong YU Mei-zi 《Animal Husbandry and Feed Science》 CAS 2010年第10期4-6,16,共4页
In order to improve the breeding effect of livestock, the data were read from an Excel file with Active Server Page (ASP) programs, and the breeding values of breeding stock were calculated by best linear unbiased p... In order to improve the breeding effect of livestock, the data were read from an Excel file with Active Server Page (ASP) programs, and the breeding values of breeding stock were calculated by best linear unbiased prediction (BLUP) method. 展开更多
关键词 Best linear unbiased prediction Active Server Paget Excel Breeding stock Breeding value
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Estimators of Linear Regression Model and Prediction under Some Assumptions Violation
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作者 Kayode Ayinde Emmanuel O. Apata Oluwayemisi O. Alaba 《Open Journal of Statistics》 2012年第5期534-546,共13页
The development of many estimators of parameters of linear regression model is traceable to non-validity of the assumptions under which the model is formulated, especially when applied to real life situation. This not... The development of many estimators of parameters of linear regression model is traceable to non-validity of the assumptions under which the model is formulated, especially when applied to real life situation. This notwithstanding, regression analysis may aim at prediction. Consequently, this paper examines the performances of the Ordinary Least Square (OLS) estimator, Cochrane-Orcutt (COR) estimator, Maximum Likelihood (ML) estimator and the estimators based on Principal Component (PC) analysis in prediction of linear regression model under the joint violations of the assumption of non-stochastic regressors, independent regressors and error terms. With correlated stochastic normal variables as regressors and autocorrelated error terms, Monte-Carlo experiments were conducted and the study further identifies the best estimator that can be used for prediction purpose by adopting the goodness of fit statistics of the estimators. From the results, it is observed that the performances of COR at each level of correlation (multicollinearity) and that of ML, especially when the sample size is large, over the levels of autocorrelation have a convex-like pattern while that of OLS and PC are concave-like. Also, as the levels of multicollinearity increase, the estimators, except the PC estimators when multicollinearity is negative, rapidly perform better over the levels autocorrelation. The COR and ML estimators are generally best for prediction in the presence of multicollinearity and autocorrelated error terms. However, at low levels of autocorrelation, the OLS estimator is either best or competes consistently with the best estimator, while the PC estimator is either best or competes with the best when multicollinearity level is high(λ>0.8 or λ-0.49). 展开更多
关键词 prediction ESTIMATORS linear Regression Model Autocorrelated Error TERMS CORRELATED Stochastic NORMAL Regressors
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Linear extrapolation for prediction of tensile creep compliance of polyvinyl chloride
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作者 谢刚 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第5期587-589,共3页
The universal creep equation is successful in relating the creep (ε) to the aging time (te), coefficient of retardation time (β), and intrinsic time (t0). This relation was used to treat the creep experiment... The universal creep equation is successful in relating the creep (ε) to the aging time (te), coefficient of retardation time (β), and intrinsic time (t0). This relation was used to treat the creep experimental data for polyvinyl chloride (PVC) specimens at a given stress and different aging times. The βgs found by the “polynomial fitting” method in this work instead of the “middle-point” method reported in the literature. The unified master line was constructed with the treated data and curves according to the universal equation. The master line can be used to predict the long-term creep behavior and lifetime by extrapolating. 展开更多
关键词 线性推断 氯化聚乙烯 PVC 塑性变形 拉伸力 老化反应
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Nonlinearly correlated failure analysis and autonomic prediction for distributed systems
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作者 Lu Xu Wang Huiqiang +2 位作者 Lv Xiao Feng Guangsheng Zhou Renjie 《High Technology Letters》 EI CAS 2011年第3期290-298,共9页
关键词 分布式系统 非线性相关 故障预测 故障分析 故障特征分析 特征提取 局部线性嵌入 识别精度
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A Study on Simple Prediction Method of Heat Load: A Use of Linear Approximation Indicial Response in Basements
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作者 Kyung-Soon Park Hiroaki Kitano Hisaya Nagai 《Journal of Civil Engineering and Architecture》 2013年第4期379-387,共9页
关键词 负荷预测 地下室 线性逼近 热负荷计算 热量条件 计算技术 热湿交换 模型预测
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AN IMPROVED 2.4kb/s MIXED EXCITATION LINEAR PREDICTION VOCODER
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作者 MaXin LiWenyuan LiuChangshu ZhangYuzhong 《Journal of Electronics(China)》 2005年第4期431-436,共6页
This letter presents two improvements on 2.4 kb/s Mixed-Excitation Linear Prediction (MELP) vocoder. The one is a new parameter Redzc named energy to differential zerocrossing rate which is used in adaptation of V/UV ... This letter presents two improvements on 2.4 kb/s Mixed-Excitation Linear Prediction (MELP) vocoder. The one is a new parameter Redzc named energy to differential zerocrossing rate which is used in adaptation of V/UV decision of transitional segments and low energy level speech segments. The other is a multi-path searching method for Multi-Stage Vector Quantization (MSVQ) of line spectral frequency. Subjective tests show that the intelligiblity and naturallity of improved MELP vocoder are preferable to those of the original one. 展开更多
关键词 MELP 声码器 MSVQ 语音编码
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Partial Linear Model Averaging Prediction for Longitudinal Data
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作者 LI Na FEI Yu ZHANG Xinyu 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2024年第2期863-885,共23页
Prediction plays an important role in data analysis.Model averaging method generally provides better prediction than using any of its components.Even though model averaging has been extensively investigated under inde... Prediction plays an important role in data analysis.Model averaging method generally provides better prediction than using any of its components.Even though model averaging has been extensively investigated under independent errors,few authors have considered model averaging for semiparametric models with correlated errors.In this paper,the authors offer an optimal model averaging method to improve the prediction in partially linear model for longitudinal data.The model averaging weights are obtained by minimizing criterion,which is an unbiased estimator of the expected in-sample squared error loss plus a constant.Asymptotic properties,including asymptotic optimality and consistency of averaging weights,are established under two scenarios:(i)All candidate models are misspecified;(ii)Correct models are available in the candidate set.Simulation studies and an empirical example show that the promise of the proposed procedure over other competitive methods. 展开更多
关键词 Asymptotic optimality longitudinal data model averaging estimator partially linear model prediction
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Environmental factors influencing snowfall and snowfall prediction in the Tianshan Mountains, Northwest China 被引量:8
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作者 ZHANG Xueting LI Xuemei +2 位作者 LI Lanhai ZHANG Shan QIN Qirui 《Journal of Arid Land》 SCIE CSCD 2019年第1期15-28,共14页
Snowfall is one of the dominant water resources in the mountainous regions and is closely related to the development of the local ecosystem and economy. Snowfall predication plays a critical role in understanding hydr... Snowfall is one of the dominant water resources in the mountainous regions and is closely related to the development of the local ecosystem and economy. Snowfall predication plays a critical role in understanding hydrological processes and forecasting natural disasters in the Tianshan Mountains, where meteorological stations are limited. Based on climatic, geographical and topographic variables at 27 meteorological stations during the cold season(October to April) from 1980 to 2015 in the Tianshan Mountains located in Xinjiang of Northwest China, we explored the potential influence of these variables on snowfall and predicted snowfall using two methods: multiple linear regression(MLR) model(a conventional measuring method) and random forest(RF) model(a non-parametric and non-linear machine learning algorithm). We identified the primary influencing factors of snowfall by ranking the importance of eight selected predictor variables based on the relative contribution of each variable in the two models. Model simulations were compared using different performance indices and the results showed that the RF model performed better than the MLR model, with a much higher R^2 value(R^2=0.74; R^2, coefficient of determination) and a lower bias error(RSR=0.51; RSR, the ratio of root mean square error to standard deviation of observed dataset). This indicates that the non-linear trend is more applicable for explaining the relationship between the selected predictor variables and snowfall. Relative humidity, temperature and longitude were identified as three of the most important variables influencing snowfall and snowfall prediction in both models, while elevation, aspect and latitude were of secondary importance, followed by slope and wind speed. These results will be beneficial to understand hydrological modeling and improve management and prediction of water resources in the Tianshan Mountains. 展开更多
关键词 SNOWFALL prediction SNOWFALL fraction random forest multiple linear regression predictor variables TIANSHAN Mountains
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