Validation and relevance assessment of volunteered geographic information in the case of forest fires

The proposed contribution describes a methodology we are testing in the framework of an exploratory research project in partnership with Google and the Land Management and Natural Hazards Unit, on the contribution of Volunteered Geographic Information (VGI) in the case-study of forest fires. The purpose of the research is to assess the value of VGI at different stages of a fire event (detection, spread, post-fire assessment) and compare this contribution with the flow of information from “official” sources as used by the European Forest Fire Information System. The paper will focus primarily on the methodology we are developing and testing to assess the fitness-for-purpose of VGI in this case-study. VGI is intrinsically heterogeneous as it is provided by different people, using different media such as photographs, text, video, and so on, and authors often overcome device limitations in imaginative and unpredictable ways. Moreover, a crisis context as Forest Fire could be particularly prone to inaccuracy, incompleteness and uncertainty. For our project we are extracting text data from Tweeter and photographs from Flickr. Our methodology for VGI Quality Control/Assessment has four main elements: (i) assessing the credibility or reputation of a source, (ii) analysing the spatial and temporal information as the locations of a source's profile, the message transmission and the content of the message itself (expressed through coordinates, links, toponyms used), (iii) manual, semi-automatic or automatic tagging of the VGI with keywords, and (iv) cross-referencing the VGI with other data related by source,
location or content.