Tag@Map: A Web-Based Application for Visually Analyzing Geographic Information through Georeferenced Tag Clouds

Abstract

In their activities of monitoring a territory and its spatio-temporal phenomena, decision makers often face problems which require rapid solutions in spite of the complexity of scenarios under investigation. Researchers from the Geographic Information domain support their activities by providing them with highly interactive visualization tools able both to synthesize information from large datasets and perform complex analytical tasks. The goal of this paper is to present a Web-based application for on-line GeoVisual Analytics which exploits the visualization capability of the Tag Cloud technique, the interaction ability of visual environments, and the Web-based data querying and accessing. The application elaborates an interactive simplified map containing a georeferenced cloud of tags, placed where the associated information is appropriate and significant. By applying semantic and geographic operators on the map tags, users are allowed to acquire information about the underlying data, useful for a better comprehension of the described phenomena. A system prototype has been realized which builds an overview of data distribution and classification expressed as a georeferenced tag cloud. It also allows users to navigate and analyze maps through zooming and filtering operations defined in agreement with Visual Analytics guidelines.