Evaluate Errors of 1-median Model: A Case Study in Spring Hill, FL, US

Where to establish new facilities has received an increasing focus among researchers. Approaches to this question depend on at least a set of three elements, namely representation of demand units, a distance metric, and a location-allocation model. Yet, the choice of these parameters may potentially generate different results leading to significant location errors. The aim of this paper is to quantify the impacts of demand units and distance metric on final location-allocation layout by applying the L-median model to locate one new facility in Spring Hill, Florida, and then provide reference when making the allocation decisions through presenting a picture to illustrate how significant the error is when different decisions are made. The results indicate that distance metric is the most significant factor. Among the four examined metrics, the closest-point distance performs the best than other metrics. On the other hand, the representation of demand units plays a less important role in our case. This research provides guidance on appropriate selection of parameters in location-allocation analysis. One conclusion is that fine demand units are adapted to accurate distance metrics, while coarse demand units to less accurate distance metrics.