Addressing Vagueness in Volunteered Geographic Information (VGI) - A Case Study

• Main Authors: DE LONGUEVILLE Bertrand, OSTLAENDER Nicole, KESKITALO E. Carina H.
• Language: English
• Published: GSDI association 2009
• Subjects: barents region; Northern Sweden; reindeer husbandry
• Online Access: https://publications.jrc.ec.europa.eu/repository/handle/JRC49078; http://www.gsdi.org/gsdiconf/gsdi11/papers/pdf/221.pdf

In times of climate change, people�s perceptions of environmental phenomena might become an invaluable source of information if shared with the general public and the scientific community (Craglia et al., 2008). Such information is generally described as VGI, which stands for "Volunteered Geographic Information". However, in the environmental field, VGI can be also understood as "Vague Geographic Information". We will explain why: firstly, many environmental phenomena, like precipitation and temperature distribution, lack a precise location and extent. Secondly, these phenomena are perceived by people, and the resulting information should be seen as perceptions, that, unlike measurements, may differ with the individual�s requirements on the environment: different individuals are affected by and notice different environmental characteristics depending on how they use the environment. Perceptions describe only a spatiotemporal and thematic snapshot of the entire phenomenon. The way in which VGI systems are built today is often based on the principle of putting pushpins on maps or on uploading GPS tracks. By doing so, VGI systems inherit the object-oriented vision of geographic information, implying a certain spatial precision. Very often VGI actually has this precision, as it is provided in form of addresses (�my house� or �my favorite coffee bar�) or as it has been encoded using a GPS device (�my street�) (Goodchild, 2007). However, as discussed in the previous paragraph, people�s perceptions of environmental phenomena might not correspond to a precise street address or point on a map. Motivated by the above said, we formulate the following research question: How can the vagueness of stakeholder�s perception of environmental phenomenon be reconciled with the �crisp objects� vision of current VGI, to build innovative VGI systems? We propose a hybrid strategy, combining an Open Gazetteer approach (Jones et al., 2008), and the concept of Degree of Truth (Fisher, 2000). The Open Gazetteer approach permits users to locate events using their own words and reference system. The concept of Degree of Truth includes elements of the fuzzy sets theory in the web based VGI system to reflect uncertainty of a given localization.The research is based on a real-world case study. Actors from forestry, fishing and reindeer husbandry sectors in the Barents region have been interviewed concerning their perception of how specific changes in climate (e.g., an earlier spring) would impact them according to their experience on the field (Keskiatlo, 2008). This data has been analyzed with respect to how people perceive and describe environmental phenomena and how they describe them, as well as which characteristics are important for them. This is the base for the proposed strategy of how to capture and represent such information. As a proof-of concept we design a web based system that can capture, store and portray this Volunteered and Vague Geographic Information, to effectively capture stakeholder testimonials on climate change. The web based system will be applied for an ongoing study of forestry, reindeer husbandry and tourism in selected locations in northern Sweden. JRC.DDG.H.6 - Spatial data infrastructures