PoD: A Web Tool for Population Downscaling Using Areal Interpolation and Volunteered Geographic Information

Population data are commonly sourced from censuses, and to meet confidentiality requirements, they are spatially aggregated into standardized enumeration units. However, the need often arises to transform such datasets into user-defined spatial scales, a process known as areal interpolation. Areal interpolation is the process of data transformation across spatial zones and is particularly suitable for aggregated data such as census data. While numerous areal interpolation methods exist, a lack of implementation tools have been witnessed. In this article, we introduce PoD, a web-based solution that encompasses four downscaling schemes. To illustrate the utility of the proposed tool, we conducted a case study using actual data from the city of Mytilini, Greece. We compared the results obtained through PoD with existing R-based implementations, in addition to evaluating their performance using a reference dataset. The outcomes of this evaluation affirm the effectivenes of the proposed PoD tool over alternative implementations.