Evaluating geospatial efficiency of facilities through Dirichlet tessellation areas and centroid proximity analysis
Abstract
Accessibility of facilities is a major component of a geospatially well-constructed community. Therefore, it is expected that proximity and access are of the most convenience to the people residing in it. For verification, an application of Dirichlet tessellation diagrams and centroid proximity can be used to give us an idea of the geographic effectiveness of a facility. We define Dirichlet tessellations as the partitioning of an area into smaller polygons which are proximal to a given set of points. For each tessellation, there exists a centroid such that every point in the partition is closer to its own tessellation than any other tessellation found in the diagram. We demonstrate this analysis using Landbank automated teller machines (ATMs) found in the National Capital Region (NCR) of the Philippines. Furthermore, we identify the Dirichlet tessellation areas and the distance of every branch with its next nearest centroid. Our analysis shows that 68% of the tessellations have a coverage area less than or equal to 1.25 km2, and 70% of the automated teller machines are within 500 m from their next nearest neighboring ATMs. It shows that there are certain places where one would have to travel farther just to reach an ATM such as residents who live far from business districts.
