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On the prediction error variance of the common spatial interpolation schemes / P.C. Kyriakidis in International journal of geographical information science IJGIS, vol 20 n° 8 (september 2006)
[article]
Titre : On the prediction error variance of the common spatial interpolation schemes Type de document : Article/Communication Auteurs : P.C. Kyriakidis, Auteur ; Michael F. Goodchild, Auteur Année de publication : 2006 Article en page(s) : pp 823 - 855 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] interpolation bilinéaire
[Termes IGN] interpolation linéaire
[Termes IGN] précision géométrique (imagerie)
[Termes IGN] propagation d'erreurRésumé : (Auteur) Three forms of linear interpolation are routinely implemented in geographical information science, by interpolating between measurements made at the endpoints of a line, the vertices of a triangle, and the vertices of a rectangle (bilinear interpolation). Assuming the linear form of interpolation to be correct, we study the propagation of error when measurement error variances and covariances are known for the samples at the vertices of these geometric objects. We derive prediction error variances associated with interpolated values at generic points in the above objects, as well as expected (average) prediction error variances over random locations in these objects. We also place all the three variants of linear interpolation mentioned above within a geostatistical framework, and illustrate that they can be seen as particular cases of Universal Kriging (UK). We demonstrate that different definitions of measurement error in UK lead to different UK variants that, for particular expected profiles or surfaces (drift models), yield weights and predictions identical with the interpolation methods considered above, but produce fundamentally different (yet equally plausible from a pure data standpoint) prediction error variances. Copyright Taylor & Francis Numéro de notice : A2006-347 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810600711279 En ligne : https://doi.org/10.1080/13658810600711279 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28071
in International journal of geographical information science IJGIS > vol 20 n° 8 (september 2006) . - pp 823 - 855[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-06081 RAB Revue Centre de documentation En réserve L003 Disponible 079-06082 RAB Revue Centre de documentation En réserve L003 Disponible Mapping the results of geographically weighted regression / J. Mennis in Cartographic journal (the), vol 43 n° 2 (July 2006)
[article]
Titre : Mapping the results of geographically weighted regression Type de document : Article/Communication Auteurs : J. Mennis, Auteur Année de publication : 2006 Article en page(s) : pp 171 - 179 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse bivariée
[Termes IGN] carte choroplèthe
[Termes IGN] densité de population
[Termes IGN] distribution spatiale
[Termes IGN] Pennsylvanie (Etats-Unis)
[Termes IGN] régression géographiquement pondéréeRésumé : (Auteur) Geographically weighted regression (GWR) is a local spatial statistical technique for exploring spatial nonstationarity. Previous approaches to mapping the results of GWR have primarily employed an equal step classification and sequential no-hue colour scheme for choropleth mapping of parameter estimates. This cartographic approach may hinder the exploration of spatial nonstationarity by inadequately illustrating the spatial distribution of the sign, magnitude, and significance of the influence of each explanatory variable on the dependent variable. Approaches for improving mapping of the results of GWR are illustrated using a case study analysis of population density-median home value relationships in Philadelphia, Pennsylvania, USA. These approaches employ data classification schemes informed by the (nonspatial) data distribution, diverging colour schemes, and bivariate choropleth mapping. Copyright British Cartographic Society Numéro de notice : A2006-611 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1179/000870406X114658 En ligne : https://doi.org/10.1179/000870406X114658 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28334
in Cartographic journal (the) > vol 43 n° 2 (July 2006) . - pp 171 - 179[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 030-06021 RAB Revue Centre de documentation En réserve L003 Disponible Deriving ground surface digital elevation models from Lidar data with geostatistics / C.D. Lloyd in International journal of geographical information science IJGIS, vol 20 n° 5 (may 2006)
[article]
Titre : Deriving ground surface digital elevation models from Lidar data with geostatistics Type de document : Article/Communication Auteurs : C.D. Lloyd, Auteur ; P.M. Atkinson, Auteur Année de publication : 2006 Article en page(s) : pp 535 - 563 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] données lidar
[Termes IGN] géostatistique
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] krigeage
[Termes IGN] lissage de données
[Termes IGN] modèle numérique de surface
[Termes IGN] modèle numérique de terrain
[Termes IGN] surface du solRésumé : (Auteur) This paper focuses on two common problems encountered when using Light Detection And Ranging (LiDAR) data to derive digital elevation models (DEMs). Firstly, LiDAR measurements are obtained in an irregular configuration and on a point, rather than a pixel, basis. There is usually a need to interpolate from these point data to a regular grid so it is necessary to identify the approaches that make best use of the sample data to derive the most accurate DEM possible. Secondly, raw LiDAR data contain information on above-surface features such as vegetation and buildings. It is often the desire to (digitally) remove these features and predict the surface elevations beneath them, thereby obtaining a DEM that does not contain any above-surface features. This paper explores the use of geostatistical approaches for prediction in this situation. The approaches used are inverse distance weighting (IDW), ordinary kriging (OK) and kriging with a trend model (KT). It is concluded that, for the case studies presented, OK offers greater accuracy of prediction than IDW while KT demonstrates benefits over OK. The absolute differences are not large, but to make the most of the high quality LiDAR data KT seems the most appropriate technique in this case. Numéro de notice : A2006-175 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1080/13658810600607337 En ligne : https://doi.org/10.1080/13658810600607337 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27902
in International journal of geographical information science IJGIS > vol 20 n° 5 (may 2006) . - pp 535 - 563[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-06051 RAB Revue Centre de documentation En réserve L003 Disponible 079-06052 RAB Revue Centre de documentation En réserve L003 Disponible Utilizing Voronoi cells of location data streams for accurate computation of aggregate functions in sensor networks / M. Sharifzadeh in Geoinformatica, vol 10 n° 1 (March - May 2006)
[article]
Titre : Utilizing Voronoi cells of location data streams for accurate computation of aggregate functions in sensor networks Type de document : Article/Communication Auteurs : M. Sharifzadeh, Auteur ; C. Shahabi, Auteur Année de publication : 2006 Conférence : ACM GIS 2004, 12th ACM symposium on geographic information systems 12/11/2004 13/11/2004 Arlington Etats-Unis Selected papers Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] agrégation spatiale
[Termes IGN] analyse comparative
[Termes IGN] diagramme de Voronoï
[Termes IGN] données vectorielles
[Termes IGN] interpolation spatiale
[Termes IGN] requête spatiale
[Termes IGN] réseau de capteurs
[Termes IGN] Triangulated Irregular NetworkRésumé : (Auteur) Sensor networks are unattended deeply distributed systems whose database schema can be conceptualized using the relational model. Aggregation queries on the data sampled at each sensor node are the main means to extract the abstract characteristics of the surrounding environment. However, the non-uniform distribution of the sensor nodes in the environment leads to inaccurate results generated by the aggregation queries. In this paper, we introduce "spatial aggregations" that take into consideration the spatial location of each measurement generated by the sensor nodes. We propose the use of spatial interpolation methods derived from the fields of spatial statistics and computational geometry to answer spatial aggregations. In particular, we study Spatial Moving Average (SMA), Voronoi Diagram and Triangulated Irregular Network (TIN). Investigating these methods for answering spatial average queries, we show that the average value on the data samples weighted by the area of the Voronoi cell of the corresponding sensor node, provides the best precision. Consequently, we introduce an algorithm to compute and maintain the accurate Voronoi cell at each sensor node while the location of the others arrive on data stream. We also propose AVC-SW, a novel algorithm to approximate this Voronoi cell over a sliding window that supports dynamism in the sensor network. To demonstrate the performance of in-network implementation of our aggregation operators, we have developed prototypes of two different approaches to distributed spatial aggregate processing. Numéro de notice : A2006-096 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/SOCIETE NUMERIQUE Nature : Article DOI : 10.1007/s10707-005-4884-y En ligne : https://doi.org/10.1007/s10707-005-4884-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27823
in Geoinformatica > vol 10 n° 1 (March - May 2006)[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-06011 RAB Revue Centre de documentation En réserve L003 Disponible Error-sensitive historical GIS: Identifying areal interpolation errors in time-series data / I.N. Gregory in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)
[article]
Titre : Error-sensitive historical GIS: Identifying areal interpolation errors in time-series data Type de document : Article/Communication Auteurs : I.N. Gregory, Auteur ; P.S. Ell, Auteur Année de publication : 2006 Article en page(s) : pp 135 - 152 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Systèmes d'information géographique
[Termes IGN] analyse diachronique
[Termes IGN] données statistiques
[Termes IGN] historique des données
[Termes IGN] interpolation spatiale
[Termes IGN] série temporelle
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Historical GIS has the potential to re-invigorate our use of statistics from historical censuses and related sources. In particular, areal interpolation can be used to create long-run time-series of spatially detailed data that will enable us to enhance significantly our understanding of geographical change over periods of a century or more. The difficulty with areal interpolation, however, is that the data that it generates are estimates which will inevitably contain some error. This paper describes a technique that allows the automated identification of possible errors at the level of the individual data values. Numéro de notice : A2006-064 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/13658810500399589 En ligne : https://doi.org/10.1080/13658810500399589 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=27791
in International journal of geographical information science IJGIS > vol 20 n° 2 (february 2006) . - pp 135 - 152[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-06021 RAB Revue Centre de documentation En réserve L003 Disponible 079-06022 RAB Revue Centre de documentation En réserve L003 Disponible The accuracy of grid digital elevation models linearly constructed from scattered sample data / F. Aguilar in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)PermalinkA hybrid interpolation method for the refinement of a regular grid digital elevation model / W.Z. Shi in International journal of geographical information science IJGIS, vol 20 n° 1 (january 2006)PermalinkOn the use of dimensioned measures of error to evaluate the performance of spatial interpolators / C.J. Willmot in International journal of geographical information science IJGIS, vol 20 n° 1 (january 2006)PermalinkStatistical analysis of environmental space-time processes / N. Le (2006)PermalinkTraitement numérique du signal / M. Bellanger (2006)PermalinkLe point sur les traitements de données GNSS en réseau pour un positionnement centimétrique temps réel de meilleure qualité / Romain Legros in XYZ, n° 105 (décembre 2005 - février 2006)PermalinkA comparative analysis of areal interpolation methods / K. Hawley in Cartography and Geographic Information Science, vol 32 n° 4 (October 2005)PermalinkOn merging high- and low-resolution DEMs from TOPSAR and SRTM using a prediction-error filter / S. Yun in IEEE Transactions on geoscience and remote sensing, vol 43 n° 7 (July 2005)PermalinkComment reproduire le MNT d'une rivière ensablée ? / B. Federici in Géomatique expert, n° 44 (01/06/2005)PermalinkGWR, MAUP et lissage par potentiels / Laure Charleux in Revue internationale de géomatique, vol 15 n° 2 (juin – août 2005)Permalink