@article{vonahn2006games,
  abstract = {Through online games, people can collectively solve large-scale computational problems. Such games constitute a general mechanism for using brain power to solve open problems. In fact, designing such a game is much like designing an algorithm - it must be proven correct, its efficiency can be analyzed, a more efficient version can supersede a less efficient one, and so on. "Games with a purpose" have a vast range of applications in areas as diverse as security, computer vision, Internet accessibility, adult content filtering, and Internet search. Any game designed to address these and other problems must ensure that game play results in a correct solution and, at the same time, is enjoyable. People will play such games to be entertained, not to solve a problem - no matter how laudable the objective},
  address = {Los Alamitos, CA, USA},
  author = {von Ahn, Luis},
  doi = {10.1109/MC.2006.196},
  interhash = {55ecea6eb606a793db8355a765facb20},
  intrahash = {0494c0c8e2c518d00017430c2b792e7e},
  issn = {0018-9162},
  journal = {Computer},
  month = jun,
  number = 6,
  pages = {92--94},
  publisher = {IEEE Computer Society Press},
  title = {Games with a Purpose},
  url = {http://www.cs.cmu.edu/~biglou/ieee-gwap.pdf},
  volume = 39,
  year = 2006
}

@inproceedings{strohmaier2010users,
  abstract = {While recent progress has been achieved in understanding the structure and dynamics of social tagging systems, we know little about the underlying user motivations for tagging, and how they influence resulting folksonomies and tags. This paper addresses three issues related to this question: 1.) What motivates users to tag resources, and in what ways is user motivation amenable to quantitative analysis? 2.) Does users' motivation for tagging vary within and across social tagging systems, and if so how? and 3.) How does variability in user motivation influence resulting tags and folksonomies? In this paper, we present measures to detect whether a tagger is primarily motivated by categorizing or describing resources, and apply the measures to datasets from 8 different tagging systems. Our results show that a) users' motivation for tagging varies not only across, but also within tagging systems, and that b) tag agreement among users who are motivated by categorizing resources is significantly lower than among users who are motivated by describing resources. Our findings are relevant for (i) the development of tag recommenders, (ii) the analysis of tag semantics and (iii) the design of search algorithms for social tagging systems.},
  address = {Washington, DC, USA},
  author = {Strohmaier, M. and Körner, C. and Kern, R.},
  booktitle = {International AAAI Conference on Weblogs and Social Media (ICWSM2010)},
  interhash = {1853d675e01d6f0c850c5adc5ca1fd3f},
  intrahash = {f2842616198c97edbccb10d24919b1ab},
  month = may,
  title = {Why do users tag? Detecting users' motivation for tagging in social tagging systems},
  url = {http://www.aaai.org/ocs/index.php/ICWSM/ICWSM10/paper/view/1497},
  year = 2010
}

@inproceedings{strohmaier2008purpose,
  abstract = {The terms that are used by users during tagging have been found to be different from the terms that are used when searching for resources, which represents a fundamental problem for search in tagging based systems. To address this problem, we propose purpose tagging as a novel kind of tagging that focuses on capturing aspects of intent rather than content. By capturing the different purposes a given resource can serve, purpose tags appear useful to mediate between the vocabulary of user intent on one hand, and the vocabulary of contents and tags provided by social software applications on the other. The paper at hand makes the following contributions: 1) It extends the set of known kinds of tags with a novel type and 2) it provides first empirical evidence of the principle feasibility of purpose tagging and its potential to facilitate goal-oriented social search in an exploratory case study.},
  address = {New York, NY, USA},
  author = {Strohmaier, Markus},
  booktitle = {SSM '08: Proceedings of the 2008 ACM Workshop on Search in Social Media},
  doi = {10.1145/1458583.1458603},
  interhash = {95ea18140b3355c6ce84486c25316a21},
  intrahash = {30ae697aebb31dfe8c507857933cf121},
  isbn = {978-1-60558-258-0},
  location = {Napa Valley, California, USA},
  pages = {35--42},
  publisher = {ACM},
  title = {Purpose tagging: capturing user intent to assist goal-oriented social search},
  url = {http://portal.acm.org/citation.cfm?id=1458603},
  year = 2008
}