A comprehensive reputation assessment framework for volunteered geographic information in crowdsensing applications

Volunteered geographic information (VGI) is the result of activities where individuals, supported by enabling technologies, behave like physical sensors by harvesting and organizing georeferenced content, usually in their surroundings. Both researchers and organizations have recognized the value of VGI content, however this content is typically heterogeneous in quality and spatial coverage. As a consequence, in order for applications to benefit from it, its quality and reliability need to be assessed in advance. This may not be easy since, typically, it is unknown how the process of collecting and organizing the VGI content has been conducted and by whom. In the literature, various proposals focus on an indirect process of quality assessment based on reputation scores. Following this perspective, the present paper provides as main contributions: (i) a multi-layer architecture for VGI which supports a process of reputation evaluation; (ii) a new comprehensive model for computing reputation scores for both VGI data and contributors, based on direct and indirect evaluations expressed by users, and including the concept of data aging; (iii) a variety of experiments evaluating the accuracy of the model. Finally, the relevance of adopting this framework is discussed via an applicative scenario for recommending tourist itineraries.