Search results for "Statistical dispersion"

showing 10 items of 44 documents

The influence of conditional conservatism on ownership dispersion: An international analysis

2013

ABSTRACTWe study the influence of conditional accounting conservatism on domestic investor diversification decisions. We argue that a conservative accounting system that promotes the dissemination of bad news and which constrains managers from engaging in opportunistic activities reduces the need for investors to concentrate their ownership, and consequently helps investors to diversify their investments. Through a country-level analysis we show that increased domestic conditional conservatism and higher domestic diversification opportunities lead to higher levels of domestic ownership diversification. Our results are robust to alternative estimates of conditional conservatism, and indicate…

Accounting conservatismEconomics and EconometricsFinancial economicsAccountingAccounting information systemDiversification (finance)Risk sharingEconomicsStatistical dispersionConservatismCapital marketFinanceSpanish Journal of Finance and Accounting / Revista Española de Financiación y Contabilidad
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Multi-model ensemble simulations of olive pollen distribution in Europe in 2014: current status and outlook

2017

"Çalışmada 29 yazar bulunmaktadır. Bu yazarlardan sadece Bursa Uludağ Üniversitesi mensuplarının girişleri yapılmıştır” The paper presents the first modelling experiment of the European-scale olive pollen dispersion, analyses the quality of the predictions, and outlines the research needs. A 6-model strong ensemble of Copernicus Atmospheric Monitoring Service (CAMS) was run throughout the olive season of 2014, computing the olive pollen distribution. The simulations have been compared with observations in eight countries, which are members of the European Aeroallergen Network (EAN). Analysis was performed for individual models, the ensemble mean and median, and for a dynamically optimised c…

Allergenic pollenAtmospheric Science010504 meteorology & atmospheric sciencesAirborne pollenEnsemble averagingDistribution (economics)olive pollen airborne pollen modeling pollen forecasting multi-ensemble data fusion aerobiologyAtmospheric model010501 environmental sciences01 natural scienceslcsh:Chemistryddc:550Ragweed; Ambrosia Artemisiifolia; PollenMathematicsDry deposition schemeLand-surface parametersBerian peninsulaEnsemble forecastingDispersionAdvection algorithmiMiljövetenskaplcsh:QC1-999EuropeAtmospheric modelingClimatologyPollenEnvironment & SustainabilityBirch pollenGlobal databaseUrbanisationEnvironmentConsistency (statistics)Environmental sciences & ecologyStatistical dispersionddc:610PrecipitationOlea-europaea0105 earth and related environmental sciencesEnsemble forecastingbusiness.industryResearchCAS - Climate Air and SustainabilityWeightingEnvironmental sciences2015 Urban Mobility & Environmentlcsh:QD1-999Meteorology & atmospheric sciencesEuropean-scale olive pollen dispersion ; European Aeroallergen Network (EAN)Long-range transportELSS - Earth Life and Social SciencesPredictionbusinessEnvironmental Scienceslcsh:PhysicsAtmospheric Chemistry and Physics
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Two-days ahead prediction of daily maximum concentrations of SO2, O3, PM10, NO2, CO in the urban area of Palermo, Italy

2007

Abstract Artificial neural networks are functional alternative techniques in modelling the intricate vehicular exhaust emission dispersion phenomenon. Pollutant predictions are notoriously complex when using either deterministic or stochastic models, which explains why this model was developed using a neural network. Neural networks have the ability to learn about non-linear relationships between the used variables. In this paper a recurrent neural network (Elman model) based forecaster for the prediction of daily maximum concentrations of SO2, O3, PM10, NO2, CO in the city of Palermo is proposed. The effectiveness of the presented forecaster was tested using a time series recorded between …

Atmospheric ScienceRecurrent neural networkArtificial neural networkCorrelation coefficientMeteorologyMean squared errorStochastic modellingForecast skillStatistical dispersionAir quality indexGeneral Environmental ScienceMathematicsAtmospheric Environment
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MACC regional multi-model ensemble simulations of birch pollen dispersion in Europe

2015

Abstract. This paper presents the first ensemble modelling experiment in relation to birch pollen in Europe. The seven-model European ensemble of MACC-ENS, tested in trial simulations over the flowering season of 2010, was run through the flowering season of 2013. The simulations have been compared with observations in 11 countries, all members of the European Aeroallergen Network, for both individual models and the ensemble mean and median. It is shown that the models successfully reproduced the timing of the very late season of 2013, generally within a couple of days from the observed start of the season. The end of the season was generally predicted later than observed, by 5 days or more…

Atmospheric Sciencemedicine.medical_specialty010504 meteorology & atmospheric sciencesUrban Mobility & EnvironmentClimateAerobiologyUrbanisation010501 environmental sciencesmedicine.disease_cause01 natural sciencesAerobiologyFloweringlcsh:ChemistryPollenddc:550medicineStatistical dispersionAerosol0105 earth and related environmental sciencesEnsemble forecastingEnsemble averageModelingEnsemble forecastingCAS - Climate Air and SustainabilityMiljövetenskaplcsh:QC1-999EuropeBirch pollenlcsh:QD1-999HabitatClimatology[SDE]Environmental SciencesPollenLate seasonEnvironmental scienceELSS - Earth Life and Social SciencesEnvironment & Sustainabilitylcsh:PhysicsEnvironmental Sciences
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An evaluation of the estimation of road traffic emission factors from tracer studies

2010

Road traffic emission factors (EFs) are one of the main sources of uncertainties in emission inventories; it is necessary to develop methods to reduce these uncertainties to manage air quality more efficiently. Recently an alternative method has been proposed to estimate the EFs. In that work the emission factors were estimated from a long term tracer study developed in Ho Chi Minh City (HCMC) Vietnam. A passive tracer was continuously emitted from a finite line source placed in one side of an urban street canyon. Simultaneously, the resulting tracer concentrations were monitored at the other side of the street. The results of this experiment were used to calculate the dispersion factors an…

Atmospheric Sciencemodel validationPart Ii010504 meteorology & atmospheric sciencesMeteorologyStreet CanyonsField010501 environmental sciencesComputational fluid dynamics01 natural sciencesLine sourceDispersion ModelsPollutant DispersionTRACER11. SustainabilityRange (statistics)Statistical dispersionEmission inventoryAir quality index0105 earth and related environmental sciencesGeneral Environmental ScienceWind tunneltracer studiesFlowbusiness.industrystreet canyon[SHS.GEO]Humanities and Social Sciences/GeographyAir-QualityParticles13. Climate actionEnvironmental scienceWind-TunnelbusinessSimulationreal-world motor vehicle emissionsComputational Fluids Dynamics (CFD)
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Análisis de las publicaciones españolas sobre Documentación e Informática Médica

1994

Se estudia la producción española de documentación e información médicas, en sus distintas áreas de especialización, hasta el año 1991. Se analiza el crecimiento de la producción de los diferentes tipos de documentos sobre la disciplina, así como las materias, instituciones de procedencia y distribución geográfica . Los resultados muestran la gran dispersión de los trabajos sobre el tema y el predominio de los estudios dedicados a la documentación clínica, producidos en instituciones hospitalarias.

Bibliometric analysisBiomedical informationLibrary scienceMedical informationLibrary and Information SciencesInformation scienceBibliography. Library science. Information resourcesGeographic distributionpublicaciones españolasGeographyDocumentationdocumentación médicabibliometríaStatistical dispersionMedical literatureZRevista Española de Documentación Científica
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The simplex dispersion ordering and its application to the evaluation of human corneal endothelia

2009

A multivariate dispersion ordering based on random simplices is proposed in this paper. Given a R^d-valued random vector, we consider two random simplices determined by the convex hulls of two independent random samples of sizes d+1 of the vector. By means of the stochastic comparison of the Hausdorff distances between such simplices, a multivariate dispersion ordering is introduced. Main properties of the new ordering are studied. Relationships with other dispersion orderings are considered, placing emphasis on the univariate version. Some statistical tests for the new order are proposed. An application of such ordering to the clinical evaluation of human corneal endothelia is provided. Di…

CombinatoricsConvex hullStatistics and ProbabilityNumerical AnalysisHausdorff distanceSimplexMultivariate random variableHausdorff spaceRegular polygonUnivariateStatistical dispersionStatistics Probability and UncertaintyMathematicsJournal of Multivariate Analysis
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The Impact of the Productivity Dispersion Across Employers on the Labor's Income Share

2016

In the present paper, I study the distribution of income across the factors of production within the canonical on-the-job search framework. I show that, by weakening the competition between employers, a mean-preserving spread of the employers' productivity distribution decreases the share of the production output that the workers receive. This result is particularly intriguing in light of the rising productivity dispersion and the declining labor share in many countries.

Competition (economics)Labour economicsbusiness.industryEconomicsProduction (economics)Factors of productionDistribution (economics)Statistical dispersionWage sharebusinessProductivitySSRN Electronic Journal
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Spreading of Competing Information in a Network

2020

We propose a simple approach to investigate the spreading of news in a network. In more detail, we consider two different versions of a single type of information, one of which is close to the essence of the information (and we call it good news), and another of which is somehow modified from some biased agent of the system (fake news, in our language). Good and fake news move around some agents, getting the original information and returning their own version of it to other agents of the network. Our main interest is to deduce the dynamics for such spreading, and to analyze if and under which conditions good news wins against fake news. The methodology is based on the use of ladder fermion…

Computer scienceGeneral Physics and Astronomylcsh:Astrophysics01 natural sciencesArticle010305 fluids & plasmas37M05Simple (abstract algebra)0103 physical scienceslcsh:QB460-466operatorial modelsStatistical dispersionStatistical physics010306 general physicslcsh:ScienceSettore MAT/07 - Fisica Matematica(<i>H</i><i>ρ</i>)-induced dynamicsSingle type37N20lcsh:QC1-99947L90spreading of newslcsh:QFake news(H ρ)-induced dynamicslcsh:Physics(Hρ)-induced dynamicsEntropy
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R Code for Hausdorff and Simplex Dispersion Orderings in the 2D Case

2010

This paper proposes a software implementation using R of the Hausdorff and simplex dispersion orderings. A copy can be downloaded from http://www.uv.es/~ayala/software/fun-disp.R . The paper provides some examples using the functions exactHausdorff for the Hausdorff dispersion ordering and the function simplex for the simplex dispersion orderings. Some auxiliary functions are commented too.

Convex hullDiscrete mathematicsSimplexMultivariate random variableMathematicsofComputing_NUMERICALANALYSISHausdorff spaceAuxiliary functionFunction (mathematics)CombinatoricsTheoryofComputation_ANALYSISOFALGORITHMSANDPROBLEMCOMPLEXITYMathematics::Metric GeometryHausdorff measureStatistical dispersionMathematics
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