Search results for "Continuous"

showing 10 items of 899 documents

Elasticity function of a discrete random variable and its properties

2017

ABSTRACTElasticity (or elasticity function) is a new concept that allows us to characterize the probability distribution of any random variable in the same way as characteristic functions and hazard and reverse hazard functions do. Initially defined for continuous variables, it was necessary to extend the definition of elasticity and study its properties in the case of discrete variables. A first attempt to define discrete elasticity is seen in Veres-Ferrer and Pavia (2014a). This paper develops this definition and makes a comparative study of its properties, relating them to the properties shown by discrete hazard and reverse hazard, as both defined in Chechile (2011). Similar to continuou…

Statistics and ProbabilityMathematical optimization021103 operations researchDiscretizationHazard ratio0211 other engineering and technologies02 engineering and technology01 natural sciencesElasticity of a functionContinuous variable010104 statistics & probabilityApplied mathematicsProbability distribution0101 mathematicsElasticity (economics)Random variableMathematicsCommunications in Statistics - Theory and Methods
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Comparative Study of Human and Automated Screening for Antinuclear Antibodies by Immunofluorescence on HEp-2 Cells

2015

Background : Several automated systems had been developed in order to reduce inter-observer variability in indirect immunofluorescence (IIF) interpretation. We aimed to evaluate the performance of a processing system in antinuclear antibodies (ANA) screening on HEp-2 cells. Patients and Methods : This study included 64 ANA-positive sera and 107 ANA-negative sera that underwent IIF on two commercial kits of HEp-2 cells (BioSystems® and Euroimmun®). IIF results were compared with a novel automated interpretation system, the “ Cyclopus CADImmuno®” (CAD). Results : All ANA-positive sera images were recognized as positive by CAD (sensitivity = 100%), while 17 (15.9%) of the ANA-negative sera ima…

Statistics and ProbabilityPathologymedicine.medical_specialtyIndirect immunofluorescenceAnti-nuclear antibodymedicine.diagnostic_testbusiness.industryConcordanceHealth InformaticsIIfImmunofluorescenceHealth Professions (miscellaneous)Settore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Continuous integrationPattern identificationAutoantibodies HEp-2 Immunofluorescence autoimmune diseases automated screening standardization.Health Information ManagementMedicineFine speckledbusinessInternational Journal of Statistics in Medical Research
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Standard forms and entanglement engineering of multimode Gaussian states under local operations

2007

We investigate the action of local unitary operations on multimode (pure or mixed) Gaussian states and single out the minimal number of locally invariant parametres which completely characterise the covariance matrix of such states. For pure Gaussian states, central resources for continuous-variable quantum information, we investigate separately the parametre reduction due to the additional constraint of global purity, and the one following by the local-unitary freedom. Counting arguments and insights from the phase-space Schmidt decomposition and in general from the framework of symplectic analysis, accompany our description of the standard form of pure n-mode Gaussian states. In particula…

Statistics and ProbabilitySchmidt decompositionGaussianGeneral Physics and AstronomyFOS: Physical sciencesQuantum entanglementUnitary statesymbols.namesakeSYSTEMSFOS: MathematicsCONTINUOUS-VARIABLESStatistical physicsQuantum informationMathematical PhysicsMathematicsQuantum PhysicsCovariance matrixStatistical and Nonlinear PhysicsInvariant (physics)QUANTUM TELEPORTATION NETWORKMathematics - Symplectic GeometryModeling and SimulationPhase spacesymbolsSymplectic Geometry (math.SG)Quantum Physics (quant-ph)Optics (physics.optics)Physics - Optics
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A new stochastic representation for the decay from a metastable state

2002

Abstract We show that a stochastic process on a complex plane can simulate decay from a metastable state. The simplest application of the method to a model in which the approach to equilibrium occurs through transitions over a potential barrier is discussed. The results are compared with direct numerical simulations of the stochastic differential equations describing system's evolution. We have found that the new method is much more efficient from computational point of view than the direct simulations.

Statistics and ProbabilityStochastic partial differential equationGeometric Brownian motionStochastic differential equationContinuous-time stochastic processQuantum stochastic calculusStochastic processLocal timeDiscrete-time stochastic processStatistical physicsCondensed Matter PhysicsMathematicsPhysica A: Statistical Mechanics and its Applications
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A Bayesian SIRS model for the analysis of respiratory syncytial virus in the region of Valencia, Spain

2014

We present a Bayesian stochastic susceptible-infected-recovered-susceptible (SIRS) model in discrete time to understand respiratory syncytial virus dynamics in the region of Valencia, Spain. A SIRS model based on ordinary differential equations has also been proposed to describe RSV dynamics in the region of Valencia. However, this continuous-time deterministic model is not suitable when the initial number of infected individuals is small. Stochastic epidemic models based on a probability of disease transmission provide a more natural description of the spread of infectious diseases. In addition, by allowing the transmission rate to vary stochastically over time, the proposed model provides…

Statistics and ProbabilityTransmission rateBayesian probabilityPosterior probabilityPrediction intervalGeneral MedicineDiscrete time and continuous timePosterior predictive distributionOrdinary differential equationQuantitative Biology::Populations and EvolutionApplied mathematicsStatistics Probability and UncertaintyDisease transmissionMathematicsBiometrical Journal
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An extended continuous mapping theorem for outer almost sure weak convergence

2019

International audience; We prove an extended continuous mapping theorem for outer almost sure weak convergence in a metric space, a notion that is used in bootstrap empirical processes theory. Then we make use of those results to establish the consistency of several bootstrap procedures in empirical likelihood theory for functional parameters.

Statistics and ProbabilityWeak convergence010102 general mathematicsContinuous mapping theorem16. Peace & justiceEmpirical measure01 natural sciences010104 statistics & probabilityMetric spaceEmpirical likelihoodConsistency (statistics)[MATH.MATH-ST]Mathematics [math]/Statistics [math.ST]Applied mathematicsStatistics::Methodology0101 mathematicsStatistics Probability and UncertaintyMathematics
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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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Syntheses of Four Enantiomers of 2,3-Diendo- and 3-Endo-aminobicyclo[2.2.2]oct-5-ene-2-exo-carboxylic Acid and Their Saturated Analogues

2013

Abstract: Ethyl 2,3- diendo -3-aminobicyclo[2.2.2]oct- 5-ene-2-carboxylate ((±)- 1 ) was resolved with O , O '-dibenzoyltartaric acid via diastere omeric salt formation. The efficient synthesis of the enantiomers of 2,3- diendo -3-aminobicyclo[2.2.2]oct- 5-ene-2-carboxylic acid ((+)- 7 and (–)- 7 ), 3- endo -aminobicyclo[2.2.2]oct-5-ene-2- exo -carboxylic acid ((+)- 5 and (–)- 5 ), cis - and trans -3-aminobicyclo[2.2.2]octa ne-2-carboxylic acid ((+)- 6 , (–)- 6 , (+)- 8 and (–)- 8 ) was achieved via isomerization, hydrogenation and hydrolysis of the corresponding esters (–)- 1 and (+)- 1 . The stereochemistry and relative configurations of the synthesized compounds were determined by NMR sp…

StereochemistryCarboxylic acidCarboxylic AcidsPharmaceutical ScienceArticleAnalytical Chemistrylcsh:QD241-441Hydrolysislcsh:Organic chemistryDrug DiscoveryMoleculePhysical and Theoretical Chemistryta116Nuclear Magnetic Resonance BiomolecularEne reactionchemistry.chemical_classificationMolecular StructureChemistryOrganic ChemistryDiastereomerresolutionconstrained chiral β-amino acidsEstersNuclear magnetic resonance spectroscopycontinuous flow hydrogenationsChemistry (miscellaneous)bicyclic β-amino acid derivativesMolecular MedicineEnantiomercontinuous flow hydrogenations<b> </b>bicyclic beta-amino acid derivativesIsomerizationconstrained chiral beta-amino acids
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Robust linear quadratic mean-field games in crowd-seeking social networks.

2013

We consider a social network where opinions evolve following a stochastic averaging process under the influence of adversarial disturbances. We provide a robust mean-field game model in the spirit of H∞-optimal control, establish existence of a mean-field equilibrium, and analyze its stochastic stability.

Stochastic controlContinuous-time stochastic processMathematical optimizationSocial networkStochastic processbusiness.industryControl (management)mean field gamesRobust controlStochastic neural networkbusinessGame theoryMathematical economicsMathematics
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A Fokker–Planck control framework for multidimensional stochastic processes

2013

AbstractAn efficient framework for the optimal control of probability density functions (PDFs) of multidimensional stochastic processes is presented. This framework is based on the Fokker–Planck equation that governs the time evolution of the PDF of stochastic processes and on tracking objectives of terminal configuration of the desired PDF. The corresponding optimization problems are formulated as a sequence of open-loop optimality systems in a receding-horizon control strategy. Many theoretical results concerning the forward and the optimal control problem are provided. In particular, it is shown that under appropriate assumptions the open-loop bilinear control function is unique. The res…

Stochastic controlMathematical optimizationContinuous-time stochastic processOptimization problemoptimal control stochastic processesStochastic processApplied MathematicsOptimal controlComputational MathematicsModel predictive controlMultidimensional stochastic processOptimal control theoryLimit cycleProbability density functionFokker–Planck equationFokker–Planck equationModel predictive controlMathematicsJournal of Computational and Applied Mathematics
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