Regional service coverage modeling

Service coverage is an often utilized concept in location modeling. Whether it be evaluating existing facilities or planning for new services, an underlying goal in many planning efforts is providing at least a minimal level of service coverage to an entire region. Examples include locating emergency medical services so as to ensure acceptable response times or siting Doppler radar stations to monitor evolving weather conditions. A challenge in addressing such problems has been how to represent a study region in a digital (or mathematical) environment. Historically, the approach taken has been to represent a region as an irregular pattern of points. These points typically correspond to centroids (or centers) of neighborhoods, towns, administrative units or census boundaries and summarize population or other service demand characteristics used in location models. A related alternative has been to represent a region as a regular pattern of points. The proliferation of geographic information systems (GIS), and the spatial data they manage, suggests that such representations may be overly simplistic in some circumstances. Further, there is increasingly an attempt to incorporate greater richness in traditional location modeling approaches. In this paper we explore coverage modeling of a region. An application focusing on siting emergency warning sirens in an urban area is used to evaluate the effectiveness of alternative coverage modeling approaches. (C) 2006 Elsevier Ltd. All rights reserved.