China
Africa
Explore chapters and articles related to this topic
Geo-Crowdsourcing
Published in Hassan A. Karimi, Advanced Location-Based Technologies and Services, 2016
Jessica G. Benner, Hassan A. Karimi
Wikimapia (http://wikimapia.org) is a geowiki that provides users with a means to “describe the whole world” as their tagline reads. On its guidelines page, Wikimapia lists its aim to “create and maintain a free, complete, multilingual, up-to-date map of the whole world.” The interface (Figure 6.1) consists of an interactive map and wild tools that support and keep track of editing. Users of Wikimapia can add point, line, and area features to the interactive map and categorize each feature using a set of categories provided by the system. Wikimapia encourages a “neutral point of view” when editing and offers a set of guidelines for users (Wikimapia 2012b). Finally, following the model of the commons, Wikimapia shares the content of its maps with developers through a free API (Wikimapia 2012a).
Prod-users of geospatial information: some legal perspectives
Published in Journal of Spatial Science, 2019
Volunteered geographic information (VGI) is ‘the widespread engagement of large numbers of private citizens, often with little in the way of formal qualifications, in the creation of geographic information’ (Goodchild 2007). The user-generated content by the VGI community has played an influential role in both production and usage and those involved have sometimes been described as prod-users (Coleman et al. 2009). The portmanteau word combining ‘production’ and ‘usage’, popularised by Bruns (2008), refers to the type of user-led content creation that takes place in online environments such as Wikipedia and more particularly Wikimapia, a project to ‘describe the whole world’ by identifying and providing detailed description of point and area features at a locality (Goodchild and Hill 2008). While there is a blurring of boundaries between producing and using, the nature and motivations of prod-users have been part of an interesting discussion by Coleman et al. (2009). A typology of tasks in crowd-sourced geographic information has been proposed which distinguishes between classification, digitisation and conflation tasks (Porto de Albuquerque et al. 2016). The need for the distinction is because of the lack of clarity of the specific types of task that volunteers can perform to derive geographic information from remotely sensed imagery, and how the quality of the produced information can be assessed for particular task types.
An evaluation of data completeness of VGI through geometric similarity assessment
Published in International Journal of Image and Data Fusion, 2018
Alireza Chehreghan, Rahim Ali Abbaspour
Conventional production of the spatial information involves a prolonged process of data collection, processing, and data propagation. This process requires costly equipment and specialists, restraining the production of the spatial information to specific centres as a consequence. Although this approach is advantaged with reliability, precision, and completeness (Flanagin and Metzger 2008), its usage is limited regarding the costly process of producing spatial information. It should be mentioned that the individuals’ tendency and the possibility of their participation in activities related to spatial information have increased with the advent of technologies such as Web 2.0 and with increase in facilities in the field of communication networks and reduction the cost of equipment such as GPS-equipped mobile phones (Goodchild 2007). This participation has led to a change in production of data from up to down (from the government to the people) to a down to up format, in which the individuals play a key role (Craglia 2007, Goodchild 2007, Haklay et al. 2008). Such data produced by the public has resulted in a concept called volunteered geographic information (VGI) (Goodchild 2007). The numbers of the projects that lend their basis to the users’ communal cooperation are increasing every day. The best example of such projects is Google Map Maker, Wikimapia, and OpenStreetMap (OSM). In the meantime, OSM has become more popular due to its widespread use, as well as the availability of information.
Satellite image analysis using crowdsourcing data for collaborative mapping: current and opportunities
Published in International Journal of Digital Earth, 2020
Wei Su, Daniel Sui, Xiaodong Zhang
With the emergence of Web 2.0, crowdsourcing has been increasingly used in satellite image analysis for collaborative mapping, as in the example of involving the public to support the efforts of experts to analyze satellite images for various applications (Maisonneuve and Chopard 2012). Collaborative mapping is the aggregation of Web mapping and user-generated content, from a group of individuals or entities, and can take several distinct forms (See, Fritz, and Leeuw 2013; Wikipedia 2016). With the growth of technology for storing and sharing maps, collaborative maps have become competitors to commercial services, in the case of OpenStreetMap (OSM), Ushahidi, GeoWiki, Wikimapia, Field Papers etc. initiatived by Google Map Maker and Yandex. Map editor, Youth Mappers, Missing Maps, Tomnod, Talking Points Collaborative Mapping. Among all the articles published during the last decade, satellite image analysis and crowdsourcing have accounted for a large share of the total applications. An analysis using the Institute of Science Information Web of Science found that, in an example of parallel evolution, 5655 articles about crowdsourcing and 24,962 articles about satellite image analysis have been published since 2006 (Figure 1). The number of crowdsourcing articles increased rapidly, from 8 articles in 2006 (when the crowdsourcing first appeared in the database) to 1690 in 2016. The number of publications about satellite image analysis increased more slowly, from 1494 in 2006–2646 in 2016. However, articles that combine these two research areas are much less common, since satellite image analysis using crowdsourcing is a new research field; thus, there have been only 31 articles since 2012.