Displaying results 1 - 8 of 12
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Weighted non-connectivity for detection of irregular clusters
Content Type: Abstract
Heuristics to detect irregularly shaped spatial clusters were reviewed recently. The spatial scan statistic is a widely used measure of the strength of clusters. However, other measures may also be useful, such as the geometric compactness… read more… Duarte et al.; licensee Emerging Health Threats Journal. www.eht-journal.org 2222 in ref. 3 and compare it with the … MA, 2009;157–82. 2 Kulldorff M. A spatial scan statistic. Comm Statist Theory Meth 1997;26:1481–96. 3 Duczmal L, … Health Threats Journal AR Duarte et al. 2011, 4:s23 www.eht-journal.org page 2/2 2323 … -
What Is the True Shape of a Disease Cluster? The Multi-Objective Genetic Scan
Content Type: Abstract
Irregularly shaped spatial disease clusters occur commonly in epidemiological studies, but their geographic delineation is poorly defined. Most current spatial scan software usually displays only one of the many possible cluster solutions with… read more… de- grees of penalization parameters imposed to the free- dom of shape [1]. Even when a fairly complete set of … algo- rithm with varying degrees of penalization, the com- plete set of solutions is found in parallel, through a … -
Non-parametric intensity bounds for the visualization of disease clusters
Content Type: Abstract
Consider the most likely disease cluster produced by any given method, like SaTScan, for the detection and inference of spatial clusters in a map divided into areas; if this cluster is found to be statistically significant, what could be… read more… et al.; licensee Emerging Health Threats Journal. www.eht-journal.org 4747 The Monte Carlo simulation requires … spatial and space-time scan statistics. Tech Rep http://www.satscan.org/ 2006. 2 Rosychuk RJ. Identifying geographic … Health Threats Journal FLP Oliveira et al. 2011, 4:s47 www.eht-journal.org page 2/2 4848 … -
Mapping the uncertainty of non-contagious disease clusters boundaries in Brazil
Content Type: Abstract
The intrinsic variability that exists in the cases counting data for aggregated-area maps amounts to a corresponding uncertainty in the delineation of the most likely cluster found by methods based on the spatial scan statistics [3]. If this cluster… read more… data were obtained from the Brazilian Ministry of Health (www.datasus.gov.br) and Brazilian Institute of Geography and Statistics (www.ibge.- gov.br). Fig. 1 presents the most likely cluster … the spatial, temporal and space-time scan statistics. [www.satscan.org]. 2. Oliveira FLP, Duczmal LH, Cançado ALF, … -
A Voronoi based scan for space-time cluster detection in point event data
Content Type: Abstract
Scan statistics are highly successful for the evaluation of space-time clusters. Recently, concepts from the graph theory were applied to evaluate the set of potential clusters. Wieland et al. introduced a graph theoretical… read more… Duczmal et al.; licensee Emerging Health Threats Journal. www.eht-journal.org 1818 at risk of 1000 individuals, 100 … Health Threats Journal LH Duczmal et al. 2011, 4:s20 www.eht-journal.org page 2/2 1919 … -
Exploring Multi-Cluster Structures with the Multi-Objective Circular Scan
Content Type: Abstract
The spatial scan statistic is the usual measure of strength of a cluster [1]. Another important measure is its geometric regularity [2]. A genetic multiobjective algorithm was developed elsewhere to identify irregularly shaped clusters [3]. A search… read more… shaped clusters. We define the circular occupation (CO) of a cluster candidate roughly as its population divided … population inside the smallest circle containing it. The CO concept, computationally faster and relying on familiar … [1] Kulldorff M, 1997. A Spatial Scan Statistic, Comm. Statist. Theory Meth., 26(6), 1481-1496. [2] Duczmal … -
Optimizing Simultaneously the Geometry and the Internal Cohesion of Clusters
Content Type: Abstract
Irregularly shaped cluster finders frequently end up with a solution consisting of a large zone z spreading through the map, which is merely a collection of the highest valued regions, but not a geographically sound cluster. One way… read more… 243-262 [3]Kulldorff M, 1997. A Spatial Scan Statistic, Comm. Statist. Theory Meth., 26(6), 1481-1496. Corresponding … -
Delineating Spatial Clusters with Artificial Neural Networks
Content Type: Abstract
Multiple or irregularly shaped spatial clusters are often found in disease or syndromic surveillance maps. We develop a novel method to delineate the contours of spatial clusters, especially when there is not a clearly dominating primary cluster,… read more… [1] Kulldorff M, 1997. A Spatial Scan Statistic, Comm. Statist. Theory Meth., 26(6), 1481-1496. [2] M. H. Fun …