The pickup problem: consumers' locational preferences in flow interception (ABSTRACT)
Zeng, W., M.J. Hodgson, and I. Castillo
published: 2009 | Research publication | Refereed Journals - ODS
Zeng, W., M.J. Hodgson, and I. Castillo (2009). "The pickup problem: consumers' locational preferences in flow interception", Geographical Analysis, 41(1):149-168. Special issue dedicated to the memory of Charles (Chuck) ReVelle, creator of the field of location analysis.
ABSTRACT: We address what we call the pickup problem wherein patrons briefly interrupt a predetermined journey to obtain a simple good, such as fast food or a video, and then resume their journey. This is a problem of the class known as flow-interception location problems. Traditional flow-interception models are used to select service locations such that the flows that are intercepted are maximized. We note that in these traditional models only flow quantities are considered and where in the journey the pickup is made is not important. However, in the real world, consumers often wish to obtain a product or service at or near a specific location along their trip. In this article, we propose a pickup model (PUP) that considers consumers' locational preferences, providing a much broader, more realistic approach than FILM (a special case of PUP) to problems in the private and public sectors. By considering which patrons are served where, PUP transforms the flow-interception location model to a flow-interception location-allocation model, providing a fruitful garden for further research. We demonstrate and apply the PUP model to morning and afternoon peak traffic flows in Edmonton, Alberta, Canada. We consider the spatial distribution characteristics and cost-effectiveness of the different scenarios representing varying consumer preferences. Our computations demonstrate that the optimal locations identified by traditional models arise solely from network flow structure, whereas the optimal locations identified by PUP result from the tradeoffs between network flow structure and the importance of proximity to preferred locations. We discover that solutions of PUP are superior to those of traditional FILM if consumers have locational preferences. The up-to-date, real world transportation networks provide a realistic test-bed for this and other models of the flow-interception type.
revised Feb 21/09