Search results for "Variable"

showing 10 items of 1674 documents

Approximations in Statistics from a Decision-Theoretical Viewpoint

1987

The approximation of the probability density p(.) of a random vector x∊X by another (possibly more convenient) probability density q(.) which belongs to a certain class Q is analyzed as a decision problem where the action space is the class Qof available approximations, the relevant uncertain event is the actual value of the vector x and the utility function is a proper scoring rule. The logarithmic divergence is shown to play a rather special role within this approach. The argument lies entirely within a Bayesian framework.

Class (set theory)Multivariate random variableScoring ruleStatisticsProbability density functionFunction (mathematics)Decision problemDivergence (statistics)MathematicsEvent (probability theory)
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Relaxation for a Class of Control Systems with Unilateral Constraints

2019

We consider a nonlinear control system involving a maximal monotone map and with a priori feedback. We assume that the control constraint multifunction $U(t,x)$ is nonconvex valued and only lsc in the $x \in \mathbb{R}^{N}$ variable. Using the Q-regularization (in the sense of Cesari) of $U(t,\cdot )$, we introduce a relaxed system. We show that this relaxation process is admissible.

Class (set theory)Partial differential equationApplied Mathematics010102 general mathematicsMaximal monotone mapNonlinear control01 natural sciencesAdmissible relaxation010101 applied mathematicsConstraint (information theory)CombinatoricsMonotone polygonQ-regularizationSettore MAT/05 - Analisi MatematicaControl systemRelaxation (approximation)0101 mathematicsLower semicontinuous multifunctionVariable (mathematics)MathematicsContinuous selection
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Are locally finite MV-algebras a variety?

2021

We answer Mundici's problem number 3 (D. Mundici. Advanced {\L}ukasiewicz calculus. Trends in Logic Vol. 35. Springer 2011, p. 235): Is the category of locally finite MV-algebras equivalent to an equational class? We prove: (i) The category of locally finite MV-algebras is not equivalent to any finitary variety. (ii) More is true: the category of locally finite MV-algebras is not equivalent to any finitely-sorted finitary quasi-variety. (iii) The category of locally finite MV-algebras is equivalent to an infinitary variety; with operations of at most countable arity. (iv) The category of locally finite MV-algebras is equivalent to a countably-sorted finitary variety. Our proofs rest upon th…

Class (set theory)Pure mathematicsAlgebra and Number Theory06D35 (Primary) 18C05 (Secondary)Duality (mathematics)Mathematics - Category TheoryMathematics - LogicArityMathematical proofComputer Science::Logic in Computer ScienceMathematics::Category TheoryFOS: MathematicsCountable setFinitaryCategory Theory (math.CT)Variety (universal algebra)Logic (math.LO)Categorical variableMathematics
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Positivity, complex FIOs, and Toeplitz operators

2018

International audience; We establish a characterization of complex linear canonical transformations that are positive with respect to a pair of strictly plurisubharmonic quadratic weights. As an application, we show that the boundedness of a class of Toeplitz operators on the Bargmann space is implied by the boundedness of their Weyl symbols.

Class (set theory)Pure mathematicsFourier integral operator in the complex domainPrimary: 32U05 32W25 35S30 47B35 70H1570H15Mathematics::Classical Analysis and ODEsOcean EngineeringCharacterization (mathematics)32U05 32W25 35S30 47B35 70H15Space (mathematics)01 natural sciencesMathematics - Analysis of PDEsQuadratic equation0103 physical sciencesFOS: Mathematics0101 mathematics[MATH]Mathematics [math]MathematicsMathematics::Functional Analysispositive canonical transformationMathematics::Complex Variables32U0532W25010102 general mathematicsToeplitz matrixFunctional Analysis (math.FA)Mathematics - Functional Analysis35S30Toeplitz operatorpositive Lagrangian plane010307 mathematical physicsstrictly plurisubharmonic quadratic form47B35Analysis of PDEs (math.AP)Toeplitz operator
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The linearized Calderón problem on complex manifolds

2019

International audience; In this note we show that on any compact subdomain of a Kähler manifold that admits sufficiently many global holomorphic functions , the products of harmonic functions form a complete set. This gives a positive answer to the linearized anisotropic Calderón problem on a class of complex manifolds that includes compact subdomains of Stein manifolds and sufficiently small subdomains of Kähler manifolds. Some of these manifolds do not admit limiting Carleman weights, and thus cannot by treated by standard methods for the Calderón problem in higher dimensions. The argument is based on constructing Morse holo-morphic functions with approximately prescribed critical points.…

Class (set theory)Pure mathematicsGeneral MathematicsHolomorphic function01 natural sciencesinversio-ongelmatSet (abstract data type)symbols.namesake[MATH.MATH-AP]Mathematics [math]/Analysis of PDEs [math.AP]0101 mathematics[MATH]Mathematics [math]complex manifoldMathematics::Symplectic GeometryMathematicsosittaisdifferentiaaliyhtälötCalderón problemMathematics::Complex VariablesApplied MathematicsRiemann surface010102 general mathematicsLimitingStandard methodsManifold010101 applied mathematicsHarmonic function[MATH.MATH-DG]Mathematics [math]/Differential Geometry [math.DG]symbolsinverse problemMathematics::Differential Geometrymonistot
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Canonical Perturbation Theory with Several Degrees of Freedom

2001

We extend the perturbation theory of the previous chapter by going one order further and permitting several degrees of freedom. So let the unperturbed problem H0(J k 0) be solved.

Classical mechanicsCanonical transformationAction variableMathematics
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Improvement of Temperature Based ANN Models for ETo Prediction in Coastal Locations by Means of Preliminary Models and Exogenous Data

2008

This paper reports the application of artificial neural networks for estimating reference evapotranspiration (ETo) as a function of local maximum and minimum air temperatures and exogenous relative humidity and evapotranspiration in twelve coastal locations of the autonomous Valencia region, Spain. The Penman-Monteith model for ETo prediction, as been proposed by the Food and Agriculture Organization of the United Nations (FAO) as the standard method for ETo forecast, has been used to provide the ANN targets. The number of stations where reliable climatic data are available for the application of the Penman-Monteith equation is limited. Thus, the development of more precise predicting tools…

Climatic dataMeteorologyArtificial neural networkEvapotranspirationClimatic variablesEnvironmental scienceAtmospheric modelPenman–Monteith equationData modeling2008 Eighth International Conference on Hybrid Intelligent Systems
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Determinants of between-hospital variations in outcomes for patients admitted with COPD exacerbations: findings from a nationwide clinical audit (AUD…

2015

Background Previous studies have demonstrated significant variability in the processes of care and outcomes of chronic obstructive pulmonary disease (COPD) exacerbations. The AUDIPOC is a Spanish nationwide clinical audit that identified large between-hospital variations in care and clinical outcomes. Here, we test the hypothesis that these variations can be attributed to either patient characteristics, hospital characteristics and/or the so-called hospital-clustering effect, which indicates that patients with similar characteristics may experience different processes of care and outcomes depending on the hospital to which they are admitted. Methods A clinical audit of 5178 COPD patients co…

Clinical auditMalePediatricsmedicine.medical_specialtyPulmonologymedia_common.quotation_subjectPsychological interventionMEDLINEPulmonary diseaseDisease clusterPatient ReadmissionAUDIPOCPulmonary Disease Chronic ObstructivemedicineOdds RatioHumansHospital Mortalitymedia_commonAgedOriginal PaperCOPDVariablesClinical Auditbusiness.industryHospitals PublicGeneral MedicineOdds ratioMiddle Agedmedicine.diseasePrognosisCOPD exacerbationsSpainEmergency medicineFemalebusiness
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Risk factors associated with adverse events in neonates with peripherally inserted central catheter

2019

Abstract Background Peripherally inserted central catheters have become a priority in infants who require long-term intravenous therapy, but their use involves certain risks. Objective The aim of the study was to describe the occurrence of adverse events in newborns with peripherally inserted central catheters and to determine the risk factors associated with them. Methods A descriptive cross-sectional study was designed and performed. All neonates with peripherally inserted central catheters from October 1st, 2014 to September 30th, 2015 were included. The adverse events and sociodemographic and clinical variables related to neonates and analysed catheters were recorded. Results A total of…

Clinical variablesbusiness.industrymedicine.medical_treatmentPeripherally inserted central catheterExtravasation03 medical and health sciencesLow birth weight0302 clinical medicineIntravenous therapy030225 pediatricsAnesthesiamedicine030212 general & internal medicinemedicine.symptombusinessAdverse effectEnfermería Intensiva (English ed.)
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Do categorical representations modulate early perceptual or later cognitive visual processing? An ERP study.

2021

Abstract Encoding of perceptual categorical information has been observed in later cognitive processing like memory encoding and maintenance, starting around 300 ms after stimulus onset (P300). However, it remains open whether categorical information is also encoded in early perceptual processing steps (reflected in the mismatch negativity component; vMMN). The main goal of this study was to assess the influence of categorical information on both early perceptual (i.e., vMMN component) and later cognitive (i.e., P300 component) processing within one paradigm. Hence, we combined an oddball paradigm with a delayed memory task. We used five-dot patterns belonging to different categories even t…

Cognitive Neurosciencemedia_common.quotation_subjectMismatch negativityExperimental and Cognitive Psychology050105 experimental psychologyVisual processing03 medical and health sciences0302 clinical medicineCognitionArts and Humanities (miscellaneous)MemoryPerceptionDevelopmental and Educational PsychologyHumans0501 psychology and cognitive sciencesOddball paradigmCategorical variablemedia_commonn-back05 social sciencesCognitionElectroencephalographyNeuropsychology and Physiological PsychologyCategorizationVisual PerceptionEvoked Potentials VisualPsychology030217 neurology & neurosurgeryPhotic StimulationCognitive psychologyBrain and cognition
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