Aggregation and ecological effects in geographically based data
Aggregation ; Demographic structure ; Model ; Spatial analysis ; Statistical bias ; Statistics ; United Kingdom
in the analysis of individual-level data can be magnified when the analysis based on aggregated data is carried out. The models provide an approach to the problem of adjusting an area-level analysis to correct for aggregation effects. The data come from the 1991
Measuring neighbourhood spatial accessibility to urban amenities : does aggregation error matter ?
Accessibility ; Aggregation ; Error ; Residential environment ; Statistics ; Urban area ; Urban district ; Urban infrastructure
data analysis techniques are used to examine aggregation-error effects on spatial accessibility.
Aggregation error arises when a single point is used to represent a neighbourhood. The spatial accessibility to three types of recreational amenities in Edmonton, is used to assess whether aggregation error affects the measures. Exploratory spatial
La résolution d'un problème de localisation à l'aide d'unités agrégées illustrant la demande introduit quelques biais statistiques qui sont sources d'erreur. Les AA. suggèrent une stratégie de contrôle de l'erreur globale.
Multiscale statistical models for hierarchical spatial aggregation
Data analysis ; Model ; Scale ; Space time ; Spatial aggregation ; Spatial analysis ; Statistics
defined partitions, corresponding to successive aggregations of an initial data space. The effects of scale associated with such aggregation are captured through a fundamental decomposition of the data likelihood.
Problème de la stabilité des solutions d'un modèle de localisation obtenues à l'aide de données agrégées. Présentation de perspectives différentes de celles des recherches antérieures. Les configurations de localisation identifiées pour des données
agrégées sont évaluées à l'aide des données désagrégées d'origine. Dans ce cas, la stabilité des solutions présente un niveau supérieur.
The effects of spatial and locational cueing on the analysis of aggregate cognitive mapping data
Aggregation ; Cartographical display ; Cognitive process ; Locality ; Methodology ; United Kingdom
Les AA. évaluent les effets de la quantité d'information spatiale et du nombre de localités mentionnées sur les résultats agrégés de données de cartographie cognitive (représentation de connaissances spatiales). Il conviendrait d'adopter une analyse
Laser diffraction analysis of the disintegration of aeolian sedimentary aggregates in water
Aeolian features ; Aeolian transport ; Aggregate ; Grain size distribution ; Methodology ; Sediment transport ; Soil erosion ; Water erosion ; X-ray diffraction analysis
A new method for the analysis of aggregate disintegration in water was tested using aeolian sediment samples. Repeated laser diffraction analysis of a single sample circulating in deionized water provides a detailed view of the changes in particle
size distribution as aggregates disintegrate. This methodology also allows experiments on the effects of water chemistry, exchangeable cation chemistry, and prewetting. The results suggest that aggregates of widely varying stabilities can occur
in a wide range of particle size classes; that is, aggregate stability may to some extent be independent of the hierarchy of aggregate sizes emphasized in earlier research. The methods described here are applicable to a wide range of soils and sediments.
The unemployment rate and the business cycle in Britain: an aggregate and regional analysis
Autoregressive process ; Business cycle ; Economic analysis ; Great Britain ; Regional economy ; Spatial aggregation ; Statistics ; Time series ; Unemployment ; United Kingdom
Aggregationanalysis ; Competition ; Economic cost ; Economic theory ; Inter-regional trade flow ; Market ; Model ; Network ; Price fixing ; Production cost ; Spatial economy
The paper formulates a theoretical framework in which the analysis starts with supplier-customer links of micro type. The AA. derive aggregate trade links between nodes in a spatial network. It is shown how affinities and barriers shape
and influence the establishment of customer links, and how this forms aggregate patterns of flows. This framework is applied to three types of models for determining trade patterns.
Towards a dynamic aggregate shopping model and its application to retail trading hour and market area analysis
Australia ; Consumer behaviour ; Gravity model ; Market area ; New South Wales ; Retail trade ; Shopping centre ; Space time ; Spatial analysis ; Sydney
La forme complexe de l'équation du supermarché sert à étudier le comportement agrégé des consommateurs. L'accent est mis sur la relation entre trajets et centres commerciaux, en tenant compte des structures spatiales et temporelles. Etude de cinq
centres commerciaux à Sydney, au cours de la période antérieure à l'introduction d'heures non réglementées (1992). La convergence spatio-temporelle du comportement agrégé des consommateurs sur ces noeuds commerciaux, montre que le coefficient de gravité