Search results for "regression trees"

showing 9 items of 9 documents

Treed Gaussian Process Regression for Solving Offline Data-Driven Continuous Multiobjective Optimization Problems

2023

Abstract For offline data-driven multiobjective optimization problems (MOPs), no new data is available during the optimization process. Approximation models (or surrogates) are first built using the provided offline data and an optimizer, e.g. a multiobjective evolutionary algorithm, can then be utilized to find Pareto optimal solutions to the problem with surrogates as objective functions. In contrast to online data-driven MOPs, these surrogates cannot be updated with new data and, hence, the approximation accuracy cannot be improved by considering new data during the optimization process. Gaussian process regression (GPR) models are widely used as surrogates because of their ability to pr…

Pareto optimalityComputational Mathematicspareto-tehokkuusgaussiset prosessitmetamodellingGaussian processeskrigingsurrogateregression treeskriging-menetelmämonitavoiteoptimointi
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Modelling landscape constraints on farmland bird species range shifts under climate change

2018

Several studies estimating the effects of global environmental change on biodiversity are focused on climate change. Yet, non-climatic factors such as changes in land cover can also be of paramount importance. This may be particularly important for habitat specialists associated with human-dominated landscapes, where land cover and climate changes may be largely decoupled. Here, we tested this idea by modelling the influence of climate, landscape composition and pattern, on the predicted future (2021–2050) distributions of 21 farmland bird species in the Iberian Peninsula, using boosted regression trees and 10-km resolution presence/absence data. We also evaluated whether habitat specialist…

0106 biological sciencesmallintaminenEnvironmental Engineering010504 meteorology & atmospheric sciencesEnvironmental changeclimate changesBoosting regression treesClimate ChangeSpecies distributionta1172BiodiversityClimate changemodelling (creation related to information)ConservationGeneralist and specialist species010603 evolutionary biology01 natural sciencesmaisemaBirdsEnvironmental ChemistryAnimalsSpecialist and generalist speciesGlobal change scenariosWaste Management and DisposalEcosystem0105 earth and related environmental sciencesbiodiversityFarmland birdsEcologySpecies diversityBiodiversityilmastonmuutoksetlandscapePollutionbiodiversiteettiGeographyHabitatSpainbirdsEnvironmental envelope modelsta1181linnutSpecies richnessEnvironmental Monitoring
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Predicting and mapping human risk of exposure to

2019

Background Tick-borne diseases have become increasingly common in recent decades and present a health problem in many parts of Europe. Control and prevention of these diseases require a better understanding of vector distribution. Aim Our aim was to create a model able to predict the distribution of Ixodes ricinus nymphs in southern Scandinavia and to assess how this relates to risk of human exposure. Methods We measured the presence of I. ricinus tick nymphs at 159 stratified random lowland forest and meadow sites in Denmark, Norway and Sweden by dragging 400 m transects from August to September 2016, representing a total distance of 63.6 km. Using climate and remote sensing environmental …

Nymphexposure riskClimateDenmarkPopulation DynamicsIxodes ricinustick-borne diseaseboosted regression treesEnvironmentScandinavian and Nordic CountriesModels Biologicalenvironmental satellite dataparasitic diseasesAnimalsHumansSwedenLyme DiseaseGeographyIxodesNorwayResearchhuman population densitypublic healthEnvironmental ExposureTick InfestationsPhylogeographyRemote Sensing TechnologySeasonsEncephalitis Tick-Bornenorthern EuropeEuro surveillance : bulletin Europeen sur les maladies transmissibles = European communicable disease bulletin
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Contributed discussion on article by Pratola

2016

The author should be commended for his outstanding contribution to the literature on Bayesian regression tree models. The author introduces three innovative sampling approaches which allow for efficient traversal of the model space. In this response, we add a fourth alternative.

Statistics and Probabilitymodel selectionMarkov Chain Monte Carlo (MCMC)Bayesian regression treeComputer scienceBig dataBayesian regression tree (BRT) modelsComputingMilieux_LEGALASPECTSOFCOMPUTINGbirth–death processMachine learningcomputer.software_genreSequential Monte Carlo methods01 natural sciencespopulation Markov chain Monte Carlo010104 statistics & probabilitysymbols.namesakebig data0502 economics and businessBayesian Regression Trees (BART)0101 mathematics050205 econometrics Bayesian treed regressionMultiple Try Metropolis algorithmsINFERÊNCIA ESTATÍSTICAbusiness.industryApplied MathematicsModel selection05 social sciencesRejection samplingData scienceVariable-order Bayesian networkTree (data structure)Tree traversalMarkov chain Monte Carlocontinuous time Markov processsymbolsArtificial intelligencebusinessBayesian linear regressioncommunication-freecomputerGibbs samplingBayesian Analysis
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A comprehensive assessment of energy efficiency of wastewater treatment plants: An efficiency analysis tree approach

2023

Producción Científica

3305.15 Ingeniería HidráulicaÁrboles de regresiónMedio ambiente Estudios de impactoEficiencia energéticaEnvironmental EngineeringRegression treesPlantas depuradoras de aguas residuales3308 Ingeniería y Tecnología del Medio AmbienteEnergia DesenvolupamentEnergy savingsPollutionAigua DepuracióEnergy efficiencyAhorro energéticoWastewater treatment plantsEnvironmental ChemistryAguas residuales DepuraciónWaste Management and DisposalScience of The Total Environment
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Estimation of total electricity consumption curves of small areas by sampling in a finite population

2016

International audience; Many studies carried out in the French electricity company EDF are based on the analysis of the total electricity consumption curves of groups of customers. These aggregated electricity consumption curves are estimated by using samples of thousands of curves measured at a small time step and collected according to a sampling design. Small area estimation is very usual in survey sampling. It is often addressed by using implicit or explicit domain models between the interest variable and the auxiliary variables. The goal here is to estimate totals of electricity consumption curves over domains or areas. Three approaches are compared: the rst one consists in modeling th…

Big dataEnergyMSC: 62H25Functional principal component analysis[MATH.MATH-ST]Mathematics [math]/Statistics [math.ST]Regression trees[ MATH.MATH-ST ] Mathematics [math]/Statistics [math.ST]Mixed modelsFunctional data[MATH.MATH-ST] Mathematics [math]/Statistics [math.ST]
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Intelligent solutions for real-life data-driven applications

2017

The subject of this thesis belongs to the topic of machine learning or, specifically, to the development of advanced methods for regression analysis, clustering, and anomaly detection. Industry is constantly seeking improved production practices and minimized production time and costs. In connection to this, several industrial case studies are presented in which mathematical models for predicting paper quality were proposed. The most important variables for the prediction models are selected based on information-theoretic measures and regression trees approach. The rest of the original papers are devoted to unsupervised machine learning. The main focus is developing advanced spectral cluster…

spectral clusteringregression treesanomaly detectionregression analysislaadunvalvontaregressioanalyysikoneoppiminenpaper machinebig datagraph segmentationcommunity detectionnetwork securityklusterianalyysitiedonlouhintatietoturvamutual informationpaperikoneetclusteringvariable selection
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Two Relevant Forecasting Problems for Practitioners in Finance: Equity Risk Premium and Non-Performing Loans

2021

The thesis aims to substantiate whether macroeconomic factors indicators are relevant to predict both in-sample and out-of-sample assets' future performance focusing on two well-studied themes in financial economics and banking: First, the ability to predict the equity risk premium, and second, the macroeconomic determinants of non-performing loans (NPL) rates. The dissertation is divided in three chapters. Chapter 1, entitled "Forecasting the equity risk premium in the European Monetary Union", investigates the capacity of multiple economic and technical variables to predict the Euro area equity risk premium. The chapter examines the performance of several variables that could be good pred…

equity risk premiumnon-performing loansforecastingUNESCO::CIENCIAS ECONÓMICASregression treesdynamic panel data:CIENCIAS ECONÓMICAS [UNESCO]asset allocation
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Robust estimation of mean electricity consumption curves by sampling for small areas in presence of missing values

2017

In this thesis, we address the problem of robust estimation of mean or total electricity consumption curves by sampling in a finite population for the entire population and for small areas. We are also interested in estimating mean curves by sampling in presence of partially missing trajectories.Indeed, many studies carried out in the French electricity company EDF, for marketing or power grid management purposes, are based on the analysis of mean or total electricity consumption curves at a fine time scale, for different groups of clients sharing some common characteristics.Because of privacy issues and financial costs, it is not possible to measure the electricity consumption curve of eac…

Linear mixed modelsSmall area estimationMissing dataRegression treesEstimation sur petits domaines[MATH.MATH-GM] Mathematics [math]/General Mathematics [math.GM]Estimateurs à noyauModèles linéaires mixtesRandom forestsBiais conditionnelsFunctional dataSurvey sampling[MATH.MATH-GM]Mathematics [math]/General Mathematics [math.GM]RobustesseDonnées fonctionnellesPlus proches voisinsForêts aléatoiresConditional biasKernel estimatorsNearest neighboursSondageDonnées manquantesRobustnessArbres de régression
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