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Testing the effects of positional uncertainty on spatial decision-making / S. Hope in International journal of geographical information science IJGIS, vol 21 n° 6-7 (july 2007)
[article]
Titre : Testing the effects of positional uncertainty on spatial decision-making Type de document : Article/Communication Auteurs : S. Hope, Auteur ; Gary J. Hunter, Auteur Année de publication : 2007 Article en page(s) : pp 645 - 665 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] aide à la décision
[Termes IGN] incertitude de position
[Termes IGN] représentation mentale spatiale
[Termes IGN] représentation spatiale
[Termes IGN] utilisateurRésumé : (Auteur) There is now increasing agreement that the uncertainty associated with spatial information should be represented to users in a manner that is comprehensive and unambiguous. To assist with this task, researchers have developed a variety of methods to portray spatial uncertainty. While there has been some testing of the effectiveness of these displays, the possible effects of such representations on decision-making have not yet been thoroughly investigated. Indeed, studies from the psychological literature indicate that people do not always make the same decisions when presented with the same information, and they can also be sensitive to the effects of presentation, task, and context. This paper examines how the use of four different methods to represent positional uncertainty can affect spatial decision-making. The authors found that extremely significant differences in participants' responses were exhibited, depending on the manner in which positional uncertainty was displayed, although little difference was observed in the ability of the participants to comprehend the four display methods. In addition, strong preferences were recorded for certain representations over others. Copyright Taylor & Francis Numéro de notice : A2007-264 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810601073273 En ligne : https://doi.org/10.1080/13658810601073273 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28627
in International journal of geographical information science IJGIS > vol 21 n° 6-7 (july 2007) . - pp 645 - 665[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07041 RAB Revue Centre de documentation En réserve L003 Disponible 079-07042 RAB Revue Centre de documentation En réserve L003 Disponible A probabilistic framework for representing and simulating uncertain environmental variables / Gerard B.M. Heuvelink in International journal of geographical information science IJGIS, vol 21 n° 5 (may 2007)
[article]
Titre : A probabilistic framework for representing and simulating uncertain environmental variables Type de document : Article/Communication Auteurs : Gerard B.M. Heuvelink, Auteur ; J. Brown, Auteur ; E. Emiel Van Loon, Auteur Année de publication : 2007 Article en page(s) : pp 497 - 513 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Information géographique
[Termes IGN] distribution, loi de
[Termes IGN] incertitude d'attribut
[Termes IGN] incertitude de position
[Termes IGN] incertitude des données
[Termes IGN] modèle stochastique
[Termes IGN] simulationRésumé : (Auteur) Understanding the limitations of environmental data is important for managing environmental systems effectively and for encouraging the responsible use of uncertain data. Explicit assessment of the uncertainties associated with environmental data, and their storage in a database, are therefore important. This paper presents a statistical framework for representing and simulating uncertain environmental variables. In general terms, an uncertain variable is completely specified by its probability distribution function (pdf). Pdfs are developed for objects with uncertain locations ('positional uncertainty') and uncertain attribute values ('attribute uncertainty'). Objects comprising multiple space-time locations are separated into 'rigid objects', where positional uncertainty cannot alter the internal geometry of the object, and 'deformable' objects, where positional uncertainty can vary between locations in one object. Statistical dependence is allowed between uncertainties in multiple locations in one object. The uncertainties associated with attribute values are also modelled with pdfs. The type and complexity of these pdfs depend upon the measurement scale and the space-time variability of the uncertain attribute. The framework is illustrated with examples. A prototype software tool for assessing uncertainties in environmental data, storing them within a database, and for generating realizations for use in Monte Carlo studies is also presented. Copyright Taylor & Francis Numéro de notice : A2007-133 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810601063951 En ligne : https://doi.org/10.1080/13658810601063951 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28496
in International journal of geographical information science IJGIS > vol 21 n° 5 (may 2007) . - pp 497 - 513[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07031 RAB Revue Centre de documentation En réserve L003 Disponible 079-07032 RAB Revue Centre de documentation En réserve L003 Disponible Assessing the certainty of locations produced by an address geocoding system / C.A. Davis in Geoinformatica, vol 11 n° 1 (March - May 2007)
[article]
Titre : Assessing the certainty of locations produced by an address geocoding system Type de document : Article/Communication Auteurs : C.A. Davis, Auteur ; Frederico Fonseca, Auteur Année de publication : 2007 Article en page(s) : pp 103 - 129 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Bases de données localisées
[Termes IGN] base de données localisées
[Termes IGN] géocodage par adresse postale
[Termes IGN] incertitude de position
[Termes IGN] système d'information géographiqueRésumé : (Auteur) Addresses are the most common georeferencing resource people use to communicate to others a location within a city. Urban GIS applications that receive data directly from citizens, or from legacy information systems, need to be able to quickly and efficiently obtain a spatial location from addresses. In this paper we understand addresses in a broader perspective, in which not only the conventional elements of postal addresses are considered, but other kinds of direct or indirect references to places, such as building names, postal codes, or telephone area codes, which are also valuable as locators to urban places. This broader view on addresses allows us to work with two perspectives. First, in the ontological definition, modeling, and implementation of an addressing database that is flexible enough to accommodate the variety of concepts and address formats used worldwide, along with direct and indirect references to places. Second, in the definition of an indicator that is able to quantify the degree of certainty that could be reached when a user-given, semi-structured address is geocoded into a spatial position, as a function of the type and completeness of the available addressing data and of the geocoding method that has been employed. This indicator, which we call Geocoding Certainty Indicator (GCI), can be used as a threshold, beyond which the geocoded event should be left out of any statistical analysis, or as a weight that allows spatial analysis methods to reduce the influence of events that have been less reliably located. In order to support geocoding activities and the determination of the GCI, we propose a conceptual schema for addressing databases. The schema is flexible enough to accommodate a variety of addressing systems, at various levels of detail, and in different countries. Our intention is to depart from the usual geocoding strategy employed in commercial GIS products, which is usually limited to the average American or British address format. The schema also extends the notion of postal address to something broader, including popular names for places, building names, reference places, and other concepts. This approach extends Simpson’s and Yu’s Comput. Environ. Urban Syst., 27: 283–307, 2003 work on postal codes to records of any kind, including place names and loosely formatted addresses. Copyright Springer Numéro de notice : A2007-167 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1007/s10707-006-0015-7 En ligne : https://doi.org/10.1007/s10707-006-0015-7 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28530
in Geoinformatica > vol 11 n° 1 (March - May 2007) . - pp 103 - 129[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 057-07011 RAB Revue Centre de documentation En réserve L003 Disponible Evaluating the uncertainty caused by Post Office Box addresses in environmental health studies: A restricted Monte Carlo approach / X. Shi in International journal of geographical information science IJGIS, vol 21 n° 3-4 (march - april 2007)
[article]
Titre : Evaluating the uncertainty caused by Post Office Box addresses in environmental health studies: A restricted Monte Carlo approach Type de document : Article/Communication Auteurs : X. Shi, Auteur Année de publication : 2007 Article en page(s) : pp 325 - 340 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications SIG
[Termes IGN] analyse de groupement
[Termes IGN] centroïde
[Termes IGN] géocodage par adresse postale
[Termes IGN] incertitude de position
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] New Hampshire (Etats-Unis)
[Termes IGN] polygone
[Termes IGN] simulationRésumé : (Auteur) A Monte Carlo approach is used to evaluate the uncertainty caused by incorporating Post Office Box (PO Box) addresses in point-cluster detection for an environmental-health study. Placing PO Box addresses at the centroids of postcode polygons in conventional geocoding can introduce significant error into a cluster analysis of the point data generated from them. In the restricted Monte Carlo method I presented in this paper, an address that cannot be matched to a precise location is assigned a random location within the smallest polygon believed to contain that address. These random locations are then combined with the locations of precisely matched addresses, and the resulting dataset is used for performing cluster analysis. After repeating this randomization-and-analysis process many times, one can use the variance in the calculated cluster evaluation statistics to estimate the uncertainty caused by the addresses that cannot be precisely matched. This method maximizes the use of the available spatial information, while also providing a quantitative estimate of the uncertainty in that utilization. The method is applied to lung-cancer data from Grafton County, New Hampshire, USA, in which the PO Box addresses account for more than half of the address dataset. The results show that less than 50% of the detected cluster area can be considered to have high certainty. Copyright Taylor & Francis Numéro de notice : A2007-114 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1080/13658810600924211 En ligne : https://doi.org/10.1080/13658810600924211 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28477
in International journal of geographical information science IJGIS > vol 21 n° 3-4 (march - april 2007) . - pp 325 - 340[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-07021 RAB Revue Centre de documentation En réserve L003 Disponible 079-07022 RAB Revue Centre de documentation En réserve L003 Disponible Super-resolution land cover mapping with indicator geostatistics / A. Boucher in Remote sensing of environment, vol 104 n° 3 (15/10/2006)
[article]
Titre : Super-resolution land cover mapping with indicator geostatistics Type de document : Article/Communication Auteurs : A. Boucher, Auteur ; P.C. Kyriakidis, Auteur Année de publication : 2006 Article en page(s) : pp 264 - 282 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] carte d'occupation du sol
[Termes IGN] Chine
[Termes IGN] delta
[Termes IGN] fleuve
[Termes IGN] géostatistique
[Termes IGN] image Landsat-TM
[Termes IGN] incertitude de position
[Termes IGN] krigeage
[Termes IGN] problème inverse
[Termes IGN] variogrammeRésumé : (Auteur) Many satellite images have a coarser spatial resolution than the extent of land cover patterns on the ground, leading to mixed pixels whose composite spectral response consists of responses from multiple land cover classes. Spectral unmixing procedures only determine the fractions of such classes within a coarse pixel without locating them in space. Super-resolution or sub-pixel mapping aims at providing a fine resolution map of class labels, one that displays realistic spatial structure (without artifact discontinuities) and reproduces the coarse resolution fractions. In this paper, existing approaches for super-resolution mapping are placed within an inverse problem framework, and a geostatistical method is proposed for generating alternative synthetic land cover maps at the fine (target) spatial resolution; these super-resolution realizations are consistent with all the information available. More precisely, indicator coKriging is used to approximate the probability that a pixel at the fine spatial resolution belongs to a particular class, given the coarse resolution fractions and (if available) a sparse set of class labels at some informed fine pixels. Such Kriging-derived probabilities are used in sequential indicator simulation to generate synthetic maps of class labels at the fine resolution pixels. This non-iterative and fast simulation procedure yields alternative super-resolution land cover maps that reproduce: (i) the observed coarse fractions, (ii) the fine resolution class labels that might be available, and (iii) the prior structural information encapsulated in a set of indicator variogram models at the fine resolution. A case study is provided to illustrate the proposed methodology using Landsat TM data from SE China. Numéro de notice : A2006-415 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2006.04.020 En ligne : https://doi.org/10.1016/j.rse.2006.04.020 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=28139
in Remote sensing of environment > vol 104 n° 3 (15/10/2006) . - pp 264 - 282[article]Quantifying DEM uncertainty and its effect on topographic parameters / S.P. Wechsler in Photogrammetric Engineering & Remote Sensing, PERS, vol 72 n° 9 (September 2006)PermalinkAngular resolution of terrestrial laser scanners / Derek D. Lichti in Photogrammetric record, vol 21 n° 114 (June - August 2006)PermalinkUncertainty analysis for soil-terrain models / T.F.A. Bishop in International journal of geographical information science IJGIS, vol 20 n° 2 (february 2006)PermalinkIndeterminacy and spatiotemporal data: Basic definitions and case study / Dieter Pfoser in Geoinformatica, vol 9 n° 3 (September - November 2005)PermalinkAssessing positional and shape accuracy of polygons in vector GIS / Atef Bel Hadj Ali (2000)PermalinkNew advances in error simulation in vector geographical databases / Olivier Bonin (2000)PermalinkData quality in geographic information / Robert Jeansoulin (1998)PermalinkUnsichere topologische Beziehungen zwischen ungenauen Flächen / Stephan Winter (1996)PermalinkPermalinkAccuracy of spatial databases / Michael F. Goodchild (1989)Permalink