Enhancing Volunteered Geographical Information (VGI) Visualization with Open Source Web-Based Software

Abstract

Recent advances in information technology such as Web mapping and location-aware mobile devices have enabled non-experts to create, use and share volumes of spatial data in an increasingly accessible fashion. Such user-generated spatial data is usually referred to as Volunteered Geographic Information (VGI). Two of the fundamental challenges associated with the exploitation of VGI relate to information overload and extraction of meaning. In order to deal with these challenges and improve the utility of VGI, this thesis investigates the potential of several interactive geovisualization techniques including filtering, dynamic spatial aggregation, linking and brushing, and tag-based visualizations. As a preliminary work to explore and structure the new research field of VGI, a framework of the different types of VGI is elaborated and followed by a review of the challenges and current solutions related to the utilization of VGI. Based on this review, a web-based prototype is developed to serve as a platform for the evaluation of selected geovisualization techniques. The prototype is then used in a series of workshops with rich citizen-generated data related to place-based community assets. The results of the case study show that the implemented geovisualization techniques enable users to find relevant subsets of information and to gain new insights on the data. Based on the potential shown by these results, future research directions are suggested.