inscription
PORTAIL D'INFORMATION GÉOGRAPHIQUE

Résultats de la recherche (2577 résultats)

Affinez votre recherche

Par Collection Par Auteur Par Date Par Sujet Par Titre
  • A distribution-free statistical method for the spatial characterization of dune granulometry : an example from the Strzelecki Desert, South Australia
  • Aeolian features ; Australia ; Barchan ; Desert ; Dune ; Grain size distribution ; Sedimentology ; South Australia ; Statistical distribution ; Statistics
  • Australie ; Barkhane ; Distribution statistique ; Dune ; Désert ; Eolien ; Granulométrie ; South Australia ; Statistique ; Sédimentologie
  • This technical communication discusses the manner in which spatial granulometric differences for barchan dunes can be confidently and accurately identified using non-parametric statistical methods.
  • Location-specific cumulative distribution function (LSCDF) : an alternative to spatial correlation analysis
  • Correlation ; Distance ; Distribution of points ; Population ; Spatial aggregation ; Spatial analysis ; Spatial distribution ; Statistics ; United States of America
  • Agrégation spatiale ; Analyse spatiale ; Corrélation ; Distance ; Distribution de points ; Distribution spatiale ; Etats-Unis ; Population ; Statistique
  • The paper presents an approach for spatial correlation analysis for count variables by comparing their cumulative spatial distributions. Using the concept of LSCDF in classical statistics, it shows that location-specific and its associated K-S-like
  • statistic, which indicate the magnitude of difference between the two spatial distributions, are highly consistent over different levels of spatial scale. The two LSCDFs can provide a geographic description of the two spatial distributions of population
  • Statistical analysis of the distribution of points on a network
  • Distance ; Distribution of points ; Location ; Nearest neighbour ; Network ; Retail trade ; Spatial analysis ; Spatial statistics ; Statistics
  • Analyse spatiale ; Commerce de détail ; Distance ; Distribution de points ; Localisation ; Plus proche voisin ; Réseau ; Statistique ; Statistique spatiale
  • Quatre méthodes statistiques pour examiner la distribution des points sur un réseau (comme les magasins le long des rues). Méthode de la distance (plus proche voisin) avec extension du plan au réseau. Mesure de l'influence respective des types de
  • rues, des éléments d'infrastructure et des divers types d'équipements collectifs sur cette distribution. Exemples empiriques.
  • Nomothetic geography revisited : statistical distributions, their underlying principles, and inequality measures
  • Czech Republic ; Environment ; Human geography ; Society ; Statistical distribution
  • Distribution statistique ; Environnement ; Géographie humaine ; Géographie nomothétique ; Irrégularité ; Société ; Tchèque république
  • The paper focuses on some issues related to regularities in the statistical distributions of various social and environmental phenomena. The interest has also been reflected in geography with a lot of activity given to the documentation
  • and c1assifcation of the regularities but less to their explanations The performance of selected parametric measures of inequality is tested with respect to data coming from differently skewed distributions. - (EN)
  • A statistical method for analyzing the spatial relationship between the distribution of activity points and the distribution of activity continuously distributed over a region
  • Distribution of points ; Fitting ; Location ; Model ; Population density ; Population distribution ; Retail trade ; Spatial interaction ; Spatial statistics ; Statistics
  • Ajustement ; Commerce de détail ; Densité de population ; Distribution de points ; Interaction spatiale ; Localisation ; Modèle ; Répartition de la population ; Statistique ; Statistique spatiale
  • Méthode statistique d'analyse de la relation spatiale entre les distributions de deux types bien différents d'activité dans une région: distributions discrète et continue. Trois modèles permettent d'illustrer cette relation puis une méthodologie est
  • proposée pour ajuster ces modèles aux données. Les techniques d'ajustement sont développées. Application aux distributions de 37 magasins et de la population dans un faubourg d'Osaka.
  • Statistical distribution of soil loss and sediment yield at Sparacia experimental area, Sicily
  • Experimental catchment ; Flood ; Italy ; Precipitation ; Runoff ; Sediment budget ; Sicilia ; Soil erosion ; Statistical distribution ; Statistics ; Water erosion ; Watershed
  • Bassin expérimental ; Bassin-versant ; Bilan sédimentaire ; Crue ; Distribution statistique ; Ecoulement ; Erosion des sols ; Erosion hydrique ; Italie ; Précipitation ; Sicilia ; Statistique
  • An analysis of the statistical distribution of event soil loss was carried out using the data collected in the period 1999–2008 at the microplots and plots of the Sparacia experimental area (Sicily, Italy). In particular, the theoretical probability
  • distribution reproducing the empirical frequency distribution of measured soil loss was established. An estimating criterion of the soil loss of a given return period was then developed. Finally, the frequency distributions of soil erosion data collected
  • Statistical test for local patterns of spatial association
  • Matrix analysis ; Methodology ; Spatial analysis ; Statistics ; Test
  • To offer a more formal approach in line with classical statistical framework, the AA. develop an exact method for computing the p-values of the local Moran's Ii, local Geary's ci, and the modified Ord and Getis G statistics based
  • on the distributional theory of quadratic forms in normal variables. Furthermore, an approximate method is also proposed to achieve a computational cost lower than the exact method. The study not only provides an exact test for local patterns of spatial association
  • , but also puts the tests of several local statistics within a unified statistical framework.
  • Determination of the confidence interval of the Wakeby distribution using order statistics
  • Ajustement ; Distribution de Wakeby ; Généralités sur la géographie ; Méthodologie ; Statistique ; Statistique de rang ; Statistique non paramétrique
  • Possibilité de déterminer explicitement la distribution de la statistique de rang (distribution de Wakeby)| détermination pratique des intervalles de confiance lorsque l'ajustement se fait à partir d'un échantillon de taille N.
  • Temporal statistics : an application in snowfall climatology
  • Analysis of snowfall data demonstrates the utility of temporal statistics for quantifying temporal and geographic variations in a climatic variable's seasonal distribution.
  • Distance ; Distribution of points ; Methodology ; Network ; Spatial statistics ; Statistics
  • Distance ; Distribution de points ; Méthodologie ; Réseau ; Statistique ; Statistique spatiale
  • L'A. présente deux méthodes statistiques (network K-function method et network cross K-function method) pour analyser la distribution de points dans un réseau. Exemple de la distribution de commerces le long d'un réseau de rues.
  • The statistical analysis through a computational method of a distribution of points in relation to its surrounding network
  • Distribution de points ; Ghum ; Généralités sur la géographie ; Indépendance ; Informatisation ; Réseau ; Statistique ; Test statistique
  • Méthode statistique pour tester si une distribution de points sur un plan est indépendante d'un élément de type-réseau. Méthode pour informatiser ce test.
  • Local spatial autocorrelation statistics: distributional issues and an application
  • AIDS ; California ; Distance ; Epidemic ; Matrix analysis ; Spatial analysis ; Spatial autocorrelation ; Spatial statistics ; Statistics ; United States of America
  • Problème de statistique spatiale particulier: pondérations non binaires autorisées, principe d'autocorrélation selon Moran. Approximation possible des seuils de signification lors des tests relatifs aux valeurs extrêmes de la distribution. Données
  • GRADISTAT : a grain size distribution and statistics package for the analysis of unconsolidated sediments
  • Computing ; Grain size distribution ; Methodology ; Sedimentology ; Statistics
  • Grain size analysis is an essential tool for classifying sedimentary environments. A computer program called GRADISTAT has been written for the rapid analysis of grain size statistics from any of the standard measuring techniques, such as sieving
  • The effects of land reform on agricultural production, employment, and income distribution: a statistical study of Mexican States 1959-69
  • A higher moment for spatial statistics
  • Ajustement ; Autocorrélation spatiale ; Distribution Pearson type 3 ; Distribution gamma ; Généralités sur la géographie ; Simulation ; Statistique ; Statistique spatiale ; Test
  • Computing ; Distribution of points ; Practical work ; Spatial analysis ; Spatial statistics ; Statistics ; Teaching of geography
  • Analyse spatiale ; Distribution de points ; Enseignement de la géographie ; Informatique ; Statistique ; Statistique spatiale ; Travaux pratiques
  • The AA. share their experience in getting students to develop basic programming skills by providing them with exercises in descriptive statistics, nearest neighbor analysis, median center of a set of points, and networks as matrices. Ideas
  • Testing a statistical curve-fitting procedure for quantifying sediment populations within multi-modal particle-size distributions
  • Experimentation ; Grain size distribution ; Sedimentology ; Software ; Statistics ; Test
  • This paper describes a series of tests designed to evaluate the capacity of a personal computer (PC) based statistical curve-fitting program called MIX to quantify composite populations within multi-modal particle-size distributions. The main
  • outcome is that MIX can very accurately describe the modal particle size and proportions of the major composite populations within a particle-size distribution. However MIX has difficulty in identifying small populations, particularly when they are located
  • in the central sections of particle-size distributions, overlain by larger populations, or when positioned in the fine tails of distributions.
  • Precipitation statistics for geomorphologists: variations on a theme by Frank Ahnert
  • Auvergne ; England ; France ; Geomorphology ; Geomorphometry ; Kenya ; Methodology ; Precipitation ; Statistics ; United Kingdom
  • A method proposed by Ahnert for magnitude-frequency analysis amounts to fitting an exponential distribution: the parameters can be specified directly as the sample mean and the known minimum value. When applied to precipitation data, the most
  • obvious comparison is with the more general gamma distribution: although fitting is technically more awkward, methods publicised here allow estimation of parameters by maximum likelihood and computations for probably plots. The exponential my be a good
  • approximation to the upper tail of a gamma distribution. The gamma distribution reduces difficulties with outliers and curvature.
  • Glacier distribution in the Alps : statistical modelling of altitude and aspect
  • Alps (The) ; Altitude ; Europe ; Glacier ; Glacier mass balance ; Model ; Snow line ; Spatial distribution ; Statistics
  • Alpes ; Altitude ; Bilan de masse ; Distribution spatiale ; Europe ; Glacier ; Limite d'enneigement ; Modèle ; Statistique
  • Bias and precision of percentiles of bulk grain size distributions
  • Carrying capacity ; Grain size distribution ; Gravel ; Methodology ; Sampling ; Sediment transport ; Sedimentology ; Statistical distribution ; Statistics ; Stream
  • Capacité de charge ; Cours d'eau ; Distribution statistique ; Echantillonnage ; Granulométrie ; Gravier ; Méthodologie ; Statistique ; Sédimentologie ; Transport sédimentaire
  • Grain size analysis is a standard tool in the study of sediments. This paper presents a method for computer sampling experiments on variability in percentiles of a bulk grain size distributions (GSD), results for commonly used size percentiles