The slides below are from my presentation in State of the Map 2010 in Girona, Spain. While the conference is about OpenStreetMap, the presentation covers a range of spatially implicint and explicit crowdsourcing projects and also activities that we carried out in Mapping for Change, which all show that unlike other crowdsourcing activities, geography (and places) are both limiting and motivating contribution to them.
In many ways, OpenStreetMap is similar to other open source and open knowledge projects, such as Wikipedia. These similarities include the patterns of contribution and the importance of participation inequalities, in which a small group of participants contribute very significantly, while a very large group of occasional participants contribute only occasionally; the general demographic of participants, with strong representation from educated young males; or the temporal patterns of engagements, in which some participants go through a peak of activity and lose interest, while a small group joins and continues to invest its time and effort to help the progress of the project. These aspects have been identified by researchers who explored volunteering and leisure activities, and crowdsourcing as well as those who explored commons-based peer production networks (Benkler & Nissenbaum 2006).
However, OpenStreetMap is a project about geography, and deals with the shape of features and information about places on the face of the Earth. Thus, the emerging question is ‘what influence does geography have on OSM?’ Does geography make some fundamental changes to the basic principles of crowdsourcing, or should OSM be treated as ‘wikipedia for maps’?
In the presentation, which is based on my work, as well as the work of Vyron Antoniou and Nama Budhathoki, we argue that geography is playing a ‘tyrannical’ role in OSM and other projects that are based on crowdsourced geographical information and shapes the nature of the project beyond what is usually accepted.
The first influence of geography is on motivation. A survey of OSM participants shows that specific geographical knowledge, which a participant acquired at first hand, and the wish to use this knowledge and see it mapped well is an important factor in participation in the project. We found that participants are driven to mapping activities by their desire to represent the places they care about and fix the errors on the map. Both of these motives require local knowledge.
A second influence is on the accuracy and completeness of coverage, with places that are highly populated, and therefore have a larger pool of potential participants, showing better coverage than suburban areas of well-mapped cities. Furthermore, there is an ongoing discussion within the OSM community about the value of mapping without local knowledge and the impact of such action on the willingness of potential contributors to fix errors and contribute to the map.
A third, and somewhat surprising, influence is the impact of mapping places that the participants haven’t or can’t visit, such as Haiti after the earthquake or Baghdad in 2007. Despite the willingness of participants to join in and help in the data collection process, the details that can be captured without being on the ground are fairly limited, even when multiple sources such as Flickr images, Google Street View and paper maps are used. The details are limited to what was captured at a certain point in time and to the limitations of the sensing device, so the mapping is, by necessity, incomplete.
We will demonstrate these and other aspects of what we termed ‘the tyranny of place’ and its impact on what can be covered by OSM without much effort and which locations will not be covered without a concentrated effort that requires some planning.