Volunteered geographic information production as a spatial process

Wikipedia is a free encyclopedia that anyone can edit and a popular example of user-generated content that includes volunteered geographic information (VGI). In this article, we present three main contributions: (1) a spatial data model and collection methods to study VGI in systems that may not explicitly support geographic data; (2) quantitative methods for measuring distance between online authors and articles; and (3) empirically calibrated results from a gravity model of the role of distance in VGI production. To model spatial processes of VGI contributors, we use an invariant exponential gravity model based on article and author proximity. We define a proximity metric called a 'signature distance' as a weighted average distance between an article and each of its authors, and we estimate the location of 2.8 million anonymous authors through IP geolocation. Our study collects empirical data directly from 21 language-specific Wikipedia databases, spanning 7 years of contributions (2001-2008) to nearly 1 million geotagged articles. We find empirical evidence that the spatial processes of anonymous contributors fit an exponential distance decay model. Our results are consistent with the prior results on information diffusion as a spatial process, but run counter to theories that a globalized Internet neutralizes distance as a determinant of social behaviors.