Search results for "Statistic"

showing 10 items of 12520 documents

Pareto frontier in economic-statistical design of a dynamic c chart

2015

The present paper proposes an economic-statistical multi-objective design procedure for a dynamic c control chart. In detail, a mixed integer non-linear constrained mathematical model is formulated to solve the treated problem, whereas the Pareto frontier is described by the ε-constraint method. To show the employment of the proposed procedure a numerical case is solved and the related considerations are given.

multi-objective designStatistical process controlε-constraint methoddynamic c chart
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An Emulator Toolbox to Approximate Radiative Transfer Models with Statistical Learning

2015

Physically-based radiative transfer models (RTMs) help in understanding the processes occurring on the Earth’s surface and their interactions with vegetation and atmosphere. When it comes to studying vegetation properties, RTMs allows us to study light interception by plant canopies and are used in the retrieval of biophysical variables through model inversion. However, advanced RTMs can take a long computational time, which makes them unfeasible in many real applications. To overcome this problem, it has been proposed to substitute RTMs through so-called emulators. Emulators are statistical models that approximate the functioning of RTMs. Emulators are advantageous in real practice because…

multi-outputComputer scienceradiative transfer modelsScienceExtrapolationemulatorMachine learningcomputer.software_genreemulator; machine learning; radiative transfer models; multi-output; ARTMO; GUI toolbox; FLEX; fluorescenceAtmosphereARTMOPartial least squares regressionRadiative transferMATLABcomputer.programming_languageArtificial neural networkbusiness.industryQStatistical modelVegetationToolboxFLEXmachine learningPrincipal component analysisGeneral Earth and Planetary SciencesfluorescenceArtificial intelligencebusinessAlgorithmcomputerGUI toolboxRemote Sensing
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Multilevel Latent Profile Analysis With Covariates : Identifying Job Characteristics Profiles in Hierarchical Data as an Example

2018

Latent profile analysis (LPA) is a person-centered method commonly used in organizational research to identify homogeneous subpopulations of employees within a heterogeneous population. However, in the case of nested data structures, such as employees nested in work departments, multilevel techniques are needed. Multilevel LPA (MLPA) enables adequate modeling of subpopulations in hierarchical data sets. MLPA enables investigation of variability in the proportions of Level 1 profiles across Level 2 units, and of Level 2 latent classes based on the proportions of Level 1 latent profiles and Level 1 ratings, and the extent to which covariates drawn from the different hierarchical levels of th…

multilevel latent profile analysisComputer scienceStrategy and ManagementGeneral Decision SciencestyöHierarchical database model0504 sociologyManagement of Technology and Innovation0502 economics and businessStatisticsCovariatetyöntekijätjob demand-control-support modelClustered dataclustered datata515Analysis of covarianceta11205 social sciences050401 social sciences methodsMixture modelprofiilit (tieto)Heterogeneous populationominaisuudetHomogeneoushierarchical structureanalyysiJob demand control support model050203 business & managementOrganizational Research Methods
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Longitudinal mediation analysis with structural and multilevel models: associational and causal perspectives

2022

multilevel modellongitudinal mediation analysistructural equation modelcausal effectseparable effectsSettore SECS-S/01 - Statistica
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Analysing SET over time using multilevel multidimensional explanatory IRT models

2013

This contribution makes an attempt to analyze students' ratings of university teaching on a broad prospective, trying to adjust the final assessment from a wide range of factors which jointly may influence the process under evaluation: academic year peculiarities, course characteristics, students' characteristics and item dimensionality. From a methodological point of view, by setting complex Item Response models as special case of Generalized Linear or Mixed Models a large flexibility is introduced in the specification of ad hoc modelling approaches for the analysis of students' ratings.

multilevellongitudinalIRTmultidimensionalMokken Scale AnalysisSettore SECS-S/05 - Statistica SocialeSettore SECS-S/01 - Statistica
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Socio-Demographic Vulnerability of Youth

2008

For a kind of inertia effect, the Italian welfare state protects today the old age too intensely while little the new risks associated with other phases of life course. Young Italians seem to suffer the actual changes: “youth remain longer in parental home and postpone the creation of its own independent life to most advanced age”. To understand the vulnerability situation increasingly widespreading among young people, it seems more and more necessary the depth analysis of the reasons and the subjective status of this discomfort that occur through a delay in transition to adulthood. In particular we study the self-perceived vulnerability situation of young Italians in the labor market (both…

multiple correspondence analysissocio-demographic vulnerabilitytransition to adulthoodSettore SECS-S/05 - Statistica Socialeyoung people
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Multiple factor analysis: principal component analysis for multitable and multiblock data sets

2013

multiple factor analysis barycentric discriminant analysis (mufabada)statis[STAT.TH] Statistics [stat]/Statistics Theory [stat.TH]principal component analysismultiblock correspondence analysisbarycentric discriminant analysis (bada)generalized procrustes analysis (gpa)[STAT.TH]Statistics [stat]/Statistics Theory [stat.TH][ STAT.TH ] Statistics [stat]/Statistics Theory [stat.TH]consensus pca[MATH.MATH-ST]Mathematics [math]/Statistics [math.ST]multiblock pcamultiple factor analysis (mfa)multiple factorial analysis[ MATH.MATH-ST ] Mathematics [math]/Statistics [math.ST]multitable pca[MATH.MATH-ST] Mathematics [math]/Statistics [math.ST]indscalmultiblock barycentric discriminant analysis (mudica)generalized singular value decomposition
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Analysis of the psicometric properties of a multiplication and division processes assessment scale

2019

Esta comunicación se encuentra disponible en la siguiente URL: http://www.infad.eu/RevistaINFAD/OJS/index.php/IJODAEP/article/view/1464/1321 Este número está dedicado a la "Psicología de la Educación y Saberes Originarios". The domain of multiplication and division operations depends on both algorithm management and the ability to identify the semantic structure of the problem and to translate it into mathematical language. Many students present difficulties in identifying the semantic structure of the problem but not applying the algorithm when the problem is presented numericaly. The aim of the study is to validate an assessment tool of the processes involved in multiplication and divisio…

multiplicationword problemStructure (mathematical logic)Matemáticas - Problemas y ejercicios.Algorithms - Problems exercises etc.algorithmComputer sciencelcsh:BF1-990Language of mathematicsDivision (mathematics)Domain (software engineering)Algebra - Problems exercises etc.Identification (information)lcsh:PsychologyMathematics - Problems exercises etc.mistakesAlgoritmos - Problemas y ejercicios.divisionMultiplicationÁlgebra - Problemas y ejercicios.ArithmeticError detection and correctionReliability (statistics)
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Factor selection procedures in a Google Earthtm aided landslide susceptibility model: application to the Beiro river basin (Spain)

2011

A procedure to select the controlling factors connected to the slope instability has been defined. It allowed to assess the landslide susceptibility in the Rio Beiro basin (about 10 km2) over the north-eastern area of the city of Granada (Spain). Field and remote (Google EarthTM) recognition techniques allowed to generate a landslide inventory consisting in 127 phenomena. Univariate tests, using both association coefficients and validation results of single parameter susceptibility models, allowed to select among 15 controlling factors the ones that resulted as good predictor variables; these have been combined for unique conditions analysis and susceptibility maps were finally prepared. In…

multivariate landslide susceptibility models conditional analysis controlling factor selection model validation Google EarthTm.geography.geographical_feature_categorySettore GEO/04 - Geografia Fisica E GeomorfologiaUnivariateDrainage basinForecast skillLandslideLandslide susceptibilityField (geography)GeographyGoodness of fitApproximation errorStatisticsCartography
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STUDY OF LARGE PELAGIC FISH LIFE-HISTORY TRAITS IN THE CENTRAL MEDITERRANEAN SEA AND PROJECTION UNDER FUTURE CLIMATE CHANGE SCENARIOS

2022

One of the most sensitive life periods for each species is the first life stages (larval and juvenile). The survival rates of pelagic fish larvae in these phases are usually very low and subject to fluctuations, consequently affecting the recruitment of new generations. From historical Tuna landing data, the stock's abundance is fluctuating, especially for Atlantic Bluefin Tuna (ABT) (Thunnus thynnus, Linnaeus, 1758) Eastern stock. It is the largest Mediterranean Tuna and one of the most expensive species in the world. Some studies hypothesized that the fluctuations are dictated by environmental factors, particularly in the early life stages. Therefore, it appears necessary to better unders…

multivariate statistical analysiLagrangian simulationichthyoplanktontunaAuxis rochei: Thunnus alalungaMediterranean Seabackward trajectoriespawning habitatspawningThunnus thynnularval habitat
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