Displaying results 1 - 7 of 7
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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 … -
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 … -
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 … -
Dual Graph Spatial Cluster Detection for Syndromic Surveillance in Networks
Content Type: Abstract
Early warning systems must not always rely on geographical proximity for modeling the spread of contagious diseases. Instead, graph structures such as airways or social networks are more adequate in those situations. Nodes,… read more… [1] Kulldorff M, 1997. A Spatial Scan Statistic, Comm. Statist. Theory Meth., 26(6), 1481-1496. [2] Duczmal … -
Geographically Meaningful Cluster Scanning Through Weak Link Correction
Content Type: Abstract
Many heuristics were developed recently to find arbitrarily shaped clusters (see review [1]). The most popular statistic is the spatial scan [2]. Nevertheless, even if all cluster solutions could be known, the problem of… read more… appear) [2]Kulldorff M, 1997. A Spatial Scan Statistic, Comm. Statist. Theory Meth., 26(6), 1481-1496. [3]Duczmal L, … -
Spatial cluster detection through constrained dynamic programming
Content Type: Abstract
The spatial scan statistic [1] is the most used measure for cluster strenght. The evaluation of all possible subsets of regions in a large dataset is computationally infeasible. Many heuristics have appeared recently to compute approximate values… read more… Cançado ALF, Duarte AR, Duczmal L, Ferreira SJ, Fonseca CM, Gontijo ECDM. Penalized likelihood and multi-objective …