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Exploring population spatial concentrations in Northern Ireland by community background and other characteristics: an application of geographically weighted spatial statistics / C.D. Lloyd in International journal of geographical information science IJGIS, vol 24 n°7-8 (july 2010)
[article]
Titre : Exploring population spatial concentrations in Northern Ireland by community background and other characteristics: an application of geographically weighted spatial statistics Type de document : Article/Communication Auteurs : C.D. Lloyd, Auteur Année de publication : 2010 Article en page(s) : pp 1193 - 1221 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] autocorrélation spatiale
[Termes IGN] géostatistique
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] interpolation par pondération de zones
[Termes IGN] Irlande du nord
[Termes IGN] pondération
[Termes IGN] population
[Termes IGN] régression géographiquement pondérée
[Termes IGN] religion
[Termes IGN] urbanisationRésumé : (Auteur) Information on how populations are spatially concentrated by different characteristics is a key means of guiding government policies in a variety of contexts, in addition to being of substantial academic interest. In particular, to reduce inequalities between groups, it is necessary to understand the characteristics of these groups in terms of their composition and their geographical structure. This article explores the degree to which the population of Northern Ireland is spatially concentrated by a range of characteristics. There is a long history of interest in residential segregation by religion in Northern Ireland; this article assesses population concentration not only by community background ('religion or religion brought up in') but also by housing tenure, employment and other socioeconomic and demographic characteristics. The spatial structure of geographical variables can be captured by a range of spatial statistics including Moran's I. Such approaches utilise information on connections between observations or the distances between them. While such approaches are conceptually an improvement on standard aspatial statistics, a logical further step is to compute statistics on a local basis on the grounds that most real-world properties are not spatially homogenous and, therefore, global measures may mask much variation. In population geography, which provides the substantive focus for this article, there are still relatively few studies that assess in depth the application of geographically weighted statistics for exploring population characteristics individually and for exploring relations between variables. This article demonstrates the value of such approaches by using a variety of geographically weighted statistical measures to explore outputs from the 2001 Census of Population of Northern Ireland. A key objective is to assess the degree to which the population is spatially divided, as judged by the selected variables. In other words, do people cluster more strongly with others who share their community background or others who have a similar socioeconomic status in some respect? The analysis demonstrates how geographically weighted statistics can be used to explore the degree to which single socioeconomic and demographic variables and relations between such variables differ at different spatial scales and at different geographical locations. For example, the results show that there are regions comprising neighbouring areas with large proportions of people from the same community background, but with variable unemployment levels, while in other areas the first case holds true but unemployment levels are consistently low. The analysis supports the contention that geographical variations in population characteristics are the norm, and these cannot be captured without using local methods. An additional methodological contribution relates to the treatment of counts expressed as percentages. Numéro de notice : A2010-326 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810903321321 En ligne : https://doi.org/10.1080/13658810903321321 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30520
in International journal of geographical information science IJGIS > vol 24 n°7-8 (july 2010) . - pp 1193 - 1221[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010041 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010042 RAB Revue Centre de documentation En réserve L003 Disponible Spatial variability of soil nutrients and GIS-based nutrient management in Yongji County, China / Qian Zhang in International journal of geographical information science IJGIS, vol 24 n°7-8 (july 2010)
[article]
Titre : Spatial variability of soil nutrients and GIS-based nutrient management in Yongji County, China Type de document : Article/Communication Auteurs : Qian Zhang, Auteur ; Z. Yang, Auteur ; Y. Li, Auteur ; et al., Auteur Année de publication : 2010 Article en page(s) : pp 965 - 981 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] azote
[Termes IGN] Chansi (Chine)
[Termes IGN] krigeage
[Termes IGN] phosphore
[Termes IGN] potassium
[Termes IGN] sol arable
[Termes IGN] système d'information géographique
[Termes IGN] variabilité
[Termes IGN] variable régionaliséeRésumé : (Auteur) Integrated nutrient management is important for sustainable agricultural production and protecting environment quality and has been widely investigated around the world. In this article the spatial variability of soil nutrients was investigated and a regionalized nutrient management system was developed using geostatistics and geographic information system technologies. A total of 511 GPS-referenced soil samples were taken in Yongji County, Shanxi province, China, and analysed for major soil nutrients: soil total nitrogen (TN), Olsen extractable phosphorus (OLSENP) and extractable potassium (EXTK). Low concentrations of nitrogen (N) and phosphorus (P) were found and they are likely to be the main limiting nutrients for crop growth in this county. Within the county moderate spatial dependence was found for all three soil variables, but at different spatial scales. The spatial distributions of TN, OLSENP and EXTK were estimated by using kriging interpolation. The cropped areas of the county were divided into fertilizer management categories consisting of four classes of TN, three classes of OLSENP and two classes of EXTK. For the targeted crop yields, regionalized fertilization maps of N, P and K in the county were produced using geographic information system. In 3-year field verification trials in two villages the crop yields of the wheat-maize rotation system increased by 10-20%, and farmers' cash income increased by 1550-2610 RMB ha-1 year-1 where regional fertilization recommendations were implemented, in comparison with traditional farmers' practices. The regionalized maps are a practical alternative to site-specific soil nutrient management approaches in areas where it is not practical, because of small farm size or other constraints, to use intensive soil sampling and chemical analyses. Numéro de notice : A2010-315 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810903257954 En ligne : https://doi.org/10.1080/13658810903257954 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30509
in International journal of geographical information science IJGIS > vol 24 n°7-8 (july 2010) . - pp 965 - 981[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010041 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010042 RAB Revue Centre de documentation En réserve L003 Disponible Effects of topographic variability and Lidar sampling density on several DEM interpolation methods / Q. Guo in Photogrammetric Engineering & Remote Sensing, PERS, vol 76 n° 6 (June 2010)
[article]
Titre : Effects of topographic variability and Lidar sampling density on several DEM interpolation methods Type de document : Article/Communication Auteurs : Q. Guo, Auteur ; W. Li, Auteur ; H. Yu, Auteur ; O. Alvarez, Auteur Année de publication : 2010 Article en page(s) : pp 701 - 712 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] classification barycentrique
[Termes IGN] densité des points
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] fonction spline d'interpolation
[Termes IGN] interpolation
[Termes IGN] interpolation inversement proportionnelle à la distance
[Termes IGN] krigeage
[Termes IGN] modèle numérique de terrain
[Termes IGN] Triangulated Irregular Network
[Termes IGN] variabilitéRésumé : (Auteur) This study aims to quantify the effects of topographic variability (measured by coefficient variation of elevation, CV) and lidar (Light Detection and Ranging) sampling density on the DEM (Digital Elevation Model) accuracy derived from several interpolation methods at different spatial resolutions. Interpolation methods include natural neighbor (NN), inverse distance weighted (IDW), triangulated irregular network (TIN), spline, ordinary kriging (OK), and universal kriging (UK). This study is unique in that a comprehensive evaluation of the combined effects of three influencing factors (CV, sampling density, and spatial resolution) on lidar-derived DEM accuracy is carried out using different interpolation methods. Results indicate that simple interpolation methods, such as IDW, NN, and TIN, are more efficient at generating DEMs from lidar data, but kriging-based methods, such as OK and UK, are more reliable if accuracy is the most important consideration. Moreover, spatial resolution also plays an important role when generating DEMs from lidar data. Our results could be used to guide the choice of appropriate lidar interpolation methods for DEM generation given the resolution, sampling density, and topographic variability. Numéro de notice : A2010-228 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.76.6.701 En ligne : https://doi.org/10.14358/PERS.76.6.701 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30422
in Photogrammetric Engineering & Remote Sensing, PERS > vol 76 n° 6 (June 2010) . - pp 701 - 712[article]Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations / S. Lyon in International journal of geographical information science IJGIS, vol 24 n° 5-6 (may 2010)
[article]
Titre : Using landscape characteristics to define an adjusted distance metric for improving kriging interpolations Type de document : Article/Communication Auteurs : S. Lyon, Auteur ; R. Sorensen, Auteur ; J. Stendahl, Auteur ; J. Seibert, Auteur Année de publication : 2010 Article en page(s) : pp 723 - 740 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Statistiques
[Termes IGN] azote
[Termes IGN] carbone
[Termes IGN] distance euclidienne
[Termes IGN] humidité du sol
[Termes IGN] interpolation
[Termes IGN] krigeage
[Termes IGN] métrique
[Termes IGN] Suède
[Termes IGN] variogrammeRésumé : (Auteur) Interpolation of point measurements using geostatistical techniques such as kriging can be used to estimate values at non-sampled locations in space. Traditional geostatistics are based on the spatial autocorrelation concept that nearby things are more related than distant things. In this study, additional information was used to modify the traditional Euclidean concept of distance into an adjusted distance metric that incorporates similarity in terms of quantifiable landscape characteristics such as topography or land use. This new approach was tested by interpolating soil moisture content, pH and carbon-to-nitrogen (C:N) ratio measured in both the mineral and the organic soil layers at a field site in central Sweden. Semivariograms were created using both the traditional distance metrics and the proposed adjusted distance metrics to carry out ordinary kriging (OK) interpolations between sampling points. In addition, kriging with external drift (KED) was used to interpolate soil properties to evaluate the ability of the adjusted distance metric to incorporate secondary data into interpolations. The new adjusted distance metric typically lowered the nugget associated with the semivariogram, thereby better representing small-scale variability in the measured data compared to semivariograms based on the traditional distance metric. The pattern of the resulting kriging interpolations using KED and OK based on the adjusted distance metric were similar because they represented secondary data and, thus, enhanced small-scale variability compared to traditional distance OK. This created interpolations that agreed better with what is expected for the real-world spatial variation of the measured properties. Based on cross-validation error, OK interpolations using the adjusted distance metric better fit observed data than either OK interpolations using traditional distance or KED. Copyright Taylor & Francis Numéro de notice : A2010-168 Affiliation des auteurs : non IGN Thématique : MATHEMATIQUE Nature : Article DOI : 10.1080/13658810903062487 En ligne : https://doi.org/10.1080/13658810903062487 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30363
in International journal of geographical information science IJGIS > vol 24 n° 5-6 (may 2010) . - pp 723 - 740[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010032 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010031 RAB Revue Centre de documentation En réserve L003 Disponible Detecting negative spatial autocorrelation in georeferenced random variables / Daniel A. Griffith in International journal of geographical information science IJGIS, vol 24 n°3-4 (march 2010)
[article]
Titre : Detecting negative spatial autocorrelation in georeferenced random variables Type de document : Article/Communication Auteurs : Daniel A. Griffith, Auteur ; Guiseppe Arbia, Auteur Année de publication : 2010 Article en page(s) : pp 417 - 437 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] agrégation spatiale
[Termes IGN] autocorrélation spatiale
[Termes IGN] distribution spatiale
[Termes IGN] inférence statistique
[Termes IGN] régression
[Termes IGN] variable aléatoire
[Termes IGN] variable régionalisée
[Termes IGN] vecteur propreRésumé : (Auteur) Negative spatial autocorrelation refers to a geographic distribution of values, or a map pattern, in which the neighbors of locations with large values have small values, the neighbors of locations with intermediate values have intermediate values, and the neighbors of locations with small values have large values. Little is known about negative spatial autocorrelation and its consequences in statistical inference in general, and regression-based inference in particular, with spatial researchers to date concentrating mostly on understanding the much more frequently encountered case of positive spatial autocorrelation. What are the spatial contexts within which negative spatial autocorrelation should be readily found? What are its inferential consequences for regression models? This paper presents selected empirical examples of negative spatial autocorrelation, adding to the slowly growing literature about this phenomenon. Copyright Taylor & Francis Numéro de notice : A2010-143 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810902832591 En ligne : http://dx.doi.org/10.1080/13658810902832591 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30338
in International journal of geographical information science IJGIS > vol 24 n°3-4 (march 2010) . - pp 417 - 437[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2010022 RAB Revue Centre de documentation En réserve L003 Disponible 079-2010021 RAB Revue Centre de documentation En réserve L003 Disponible Optimization of mobile radioactivity monitoring networks / Gerard B.M. Heuvelink in International journal of geographical information science IJGIS, vol 24 n°3-4 (march 2010)PermalinkAccuracy 2010 : Proceedings of the Ninth international symposium on spatial accuracy assessment in natural resources and environmental sciences, Leicester, UK, 20 - 23 juillet 2010 / Nicholas J. Tate (2010)PermalinkSpatial interpolation in wireless sensor networks: localized algorithms for variogram modeling and kriging / M. Umer in Geoinformatica, vol 14 n° 1 (January 2010)PermalinkFinding appropriate interpolation techniques for topographic surface generation for mudslide risk zonation / A. Vansarochana in Geocarto international, vol 24 n° 4 (August - September 2009)PermalinkThe effects of quality control on decreasing error propagation in the LandScan USA population distribution model: a case study of Philadelphia County / L. Patterson in Transactions in GIS, vol 13 n° 2 (April 2009)PermalinkSpatiotemporal analysis of rural-urban land conversion / B. Huang in International journal of geographical information science IJGIS, vol 23 n°3-4 (march - april 2009)PermalinkPotential productivity of forested areas based on a biophysical model. A case study of a mountainous region in northern Spain / Raquel Benavides in Annals of Forest Science, Vol 66 n° 1 (January - February 2009)PermalinkUnsing spatial continuity and discontinuity information to retrieve geographic entities / Z. Xie in Geocarto international, vol 24 n° 1 (February - March 2009)PermalinkEstimating sea floor dynamics in the southern North Sea to improve bathymetric survey planning / L. Dorst (2009)PermalinkGeostastical modeling of sedimentological parameters using multi-scale terrain variables: application along the Belgian part of the North sea / Els Verfaillie in International journal of geographical information science IJGIS, vol 23 n° 1-2 (january 2009)Permalink