Search results for "Lua"

showing 10 items of 3286 documents

Ensemble Feature Selection Based on the Contextual Merit

2001

Recent research has proved the benefits of using ensembles of classifiers for classification problems. Ensembles constructed by machine learning methods manipulating the training set are used to create diverse sets of accurate classifiers. Different feature selection techniques based on applying different heuristics for generating base classifiers can be adjusted to specific domain characteristics. In this paper we consider and experiment with the contextual feature merit measure as a feature selection heuristic. We use the diversity of an ensemble as evaluation function in our new algorithm with a refinement cycle. We have evaluated our algorithm on seven data sets from UCI. The experiment…

Training setComputer sciencebusiness.industryHeuristicPattern recognitionFeature selectionContext (language use)Machine learningcomputer.software_genreEvaluation functionComputingMethodologies_PATTERNRECOGNITIONEnsembles of classifiersFeature (computer vision)Artificial intelligenceHeuristicsbusinesscomputer
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The Best Hedging Strategy in the Presence of Transaction Costs

2009

Considerable theoretical work has been devoted to the problem of option pricing and hedging with transaction costs. A variety of methods have been suggested and are currently being used for dynamic hedging of options in the presence of transaction costs. However, very little was done on the subject of an empirical comparison of different methods for option hedging with transaction costs. In a few existing studies the different methods are compared by studying their empirical performances in hedging only a plain-vanilla short call option. The reader is tempted to assume that the ranking of the different methods for hedging any kind of option remains the same as that for a vanilla call. The …

Transaction costActuarial scienceEmpirical comparisonComputer scienceVariety (cybernetics)MicroeconomicsOption hedging transaction costs simulations risk-return tradeoff optimizationRankingValuation of optionsReplicating portfolioEconometricsPosition (finance)Call optionBusinessGeneral Economics Econometrics and FinanceFinanceSSRN Electronic Journal
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Option Pricing and Hedging in the Presence of Transaction Costs and Nonlinear Partial Differential Equations

2008

In the presence of transaction costs the perfect option replication is impossible which invalidates the celebrated Black and Scholes (1973) model. In this chapter we consider some approaches to option pricing and hedging in the presence of transaction costs. The distinguishing feature of all these approaches is that the solution for the option price and hedging strategy is given by a nonlinear partial differential equation (PDE). We start with a review of the Leland (1985) approach which yields a nonlinear parabolic PDE for the option price, one of the first such in finance. Since the Leland's approach to option pricing has been criticized on different grounds, we present a justification of…

Transaction costAsymptotic analysisMathematical optimizationActuarial scienceValuation of optionsEconomicsPortfolioAsian optionBlack–Scholes modelFinite difference methods for option pricingFutures contractSSRN Electronic Journal
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European Option Pricing with Transaction Costs and Stochastic Volatility: an Asymptotic Analysis

2015

In this paper the valuation problem of a European call option in presence of both stochastic volatility and transaction costs is considered. In the limit of small transaction costs and fast mean reversion, an asymptotic expression for the option price is obtained. While the dominant term in the expansion it is shown to be the classical Black and Scholes solution, the correction terms appear at $O(\varepsilon^{1/2})$ and $O(\varepsilon)$. The optimal hedging strategy is then explicitly obtained for the Scott's model.

Transaction costAsymptotic analysisStochastic volatilityAsymptotic AnalysisApplied MathematicsStochastic VolatilityBlack–Scholes modelDynamical Systems (math.DS)Implied volatilityTransaction CostsFOS: Economics and businessOption Pricing; Stochastic Volatility; Transaction Costs; Asymptotic AnalysisValuation of optionstransaction costEconometricsMean reversionFOS: MathematicsCall optionPricing of Securities (q-fin.PR)Mathematics - Dynamical SystemsOption PricingSettore MAT/07 - Fisica MatematicaQuantitative Finance - Pricing of SecuritiesMathematics
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When a virus (Covid-19) attacks human rights: The situation of asylum seekers in the medico-legal setting

2020

The Covid-19 pandemic is a global health emergency that requires immediate, effective action by governments to protect the health and basic human rights of everyone’s life. Refugees and migrants are potentially at increased risk because they typically live in overcrowded conditions often without access to basic sanitation. Since the beginning of the official lockdown for Covid-19, the medico-legal assessment of physical violence related to obtaining status or other forms of human protection has been frozen.

Transients and MigrantsMedico legalJurisprudenceRefugeesHuman RightsCoronavirus disease 2019 (COVID-19)Human rightsSanitationRefugeemedia_common.quotation_subjectCOVID-19General MedicineCriminologyHealth Services Accessibility03 medical and health sciences0302 clinical medicineIncreased riskPolitical sciencePandemicGlobal healthHumansAsylum seekers human rights medico-legal evaluation containment measures030216 legal & forensic medicine030212 general & internal medicinemedia_commonMedico-Legal Journal
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The value of time and transport policies in a parallel road network

2007

Abstract One of the key questions in the evaluation of transport policies and investment decisions is the valuation of the time savings or losses arising from such decisions. This paper uses the stated preference method to determine the value of time in a given traffic context characterised by a road parallel network. The values obtained are higher than usual in Spanish project evaluation which, among other things, points out the need for specific studies of all transport projects whenever possible. Finally, two cases are described which illustrate the relevance of the value of time. The first evaluates time savings related to the pricing policies of a motorway competing with a trunk road. …

Transport engineeringInvestment decisionsCarriagewayTrunk roadGeography Planning and DevelopmentEconomicsTransportationRoad pricingValue of timeTransport economicsDual carriagewayValuation (finance)Transport Policy
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First mass measurement at JYFLTRAP

2004

The first mass measurements at JYFLTRAP facility are reviewed. Those are also first ever direct mass measurements of the heaviest Zr-isotopes. Results are compared to atomic mass evaluation data and the recent calculations. The first TOF-resonances from high-precision trap and an implication to high-precision mass measurements are discussed.

Trap (computing)PhysicsNuclear physicsNuclear and High Energy PhysicsEvaluation dataAtomic physicsNuclear ExperimentMass measurementAtomic massNuclear Physics A
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Optimization Strategy of Novel Peptide-Based Michael Acceptors for the Treatment of Human African Trypanosomiasis

2019

This paper describes an optimization strategy of the highly active vinyl ketone 3 which was recognized as a strong inhibitor of rhodesain of Trypanosoma brucei rhodesiense, endowed with a ksecond v...

Trypanosoma brucei rhodesienseStrong inhibitorKetoneStereochemistryProtein ConformationPeptide01 natural sciences03 medical and health sciencesStructure-Activity RelationshipSUBSTRATEDrug DiscoverymedicineHumansAfrican trypanosomiasisSulfonesBIOLOGICAL EVALUATION030304 developmental biologyWARHEADchemistry.chemical_classification0303 health sciencesMolecular StructureChemistryDERIVATIVESTrypanosoma brucei rhodesienseCYSTEINE PROTEASES RHODESAIN BIOLOGICAL EVALUATION CATHEPSIN-L INHIBITORS BRUCEI PEPTIDOMIMETICS FALCIPAIN-2 DERIVATIVES SUBSTRATE WARHEADBRUCEImedicine.diseaseFALCIPAIN-2Trypanocidal Agents0104 chemical sciences010404 medicinal & biomolecular chemistryCysteine EndopeptidasesTrypanosomiasis AfricanCYSTEINE PROTEASES RHODESAINCATHEPSIN-LMolecular MedicineINHIBITORSPEPTIDOMIMETICS
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Structure-based engineering of strictosidine synthase: auxiliary for alkaloid libraries.

2007

SummaryThe highly substrate-specific strictosidine synthase (EC 4.3.3.2) catalyzes the biological Pictet-Spengler condensation between tryptamine and secologanin, leading to the synthesis of about 2000 monoterpenoid indole alkaloids in higher plants. The crystal structure of Rauvolfia serpentina strictosidine synthase (STR1) in complex with strictosidine has been elucidated here, allowing the rational site-directed mutation of the active center of STR1 and resulting in modulation of its substrate acceptance. Here, we report on the rational redesign of STR1 by generation of a Val208Ala mutant, further describing the influence on substrate acceptance and the enzyme-catalyzed synthesis of 10-m…

TryptamineCHEMBIOLStrictosidine synthaseMICROBIOStereochemistryProtein ConformationClinical BiochemistryMutantDrug Evaluation PreclinicalMutation MissenseCrystallography X-RayProtein EngineeringBiochemistryIndole AlkaloidsSubstrate Specificitychemistry.chemical_compoundRauvolfia serpentinaDrug DiscoveryCatharanthusCarbon-Nitrogen LyasesMolecular BiologyVinca AlkaloidsPlant ProteinsPharmacologybiologyMolecular StructureGeneral Medicinebiology.organism_classificationLyaseBiochemistrychemistryStrictosidinebiology.proteinMutagenesis Site-DirectedMolecular MedicineSecologaninProtein BindingChemistrybiology
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Evaluation and Accreditation System of External Internship Tutors - SEATPE

2020

La Universidad de Valencia ha implementado desde 2012 un Sistema de Evaluación y Acreditación de Tutores de Pasantías Externas (SEATPE) a través de su Fundación Universidad-Empresa, ADEIT, bajo la dirección del Vicerrector de Empleo y Programas Formativos. Los objetivos principales de este sistema son mejorar la calidad de la tutoría de pasantías externas implementando mecanismos para reconocer el buen trabajo de los tutores y aumentar el compromiso de las empresas y entidades con la capacitación práctica de nuestros estudiantes. Está dirigido a los dos perfiles de tutores: académicos y empresas. Los tutores que acceden al SEATPE obtienen una "Mención de calidad" en el caso del tutor académ…

Tutor´s trainingMedical educationHigher educationbusiness.industryTeachingPracticumTutoringmedia_common.quotation_subjectEducational systemsPracticumHigher EducationQualityInternshipExternal internshipsLearningQuality (business)EvaluationPsychologybusinessEducational systemsAccreditationmedia_common6th International Conference on Higher Education Advances (HEAd'20)
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