Crowdsourcing has become an increasingly popular means of flexibly deploying large amounts of human computational power. The present chapter investigates the role of microtask labor marketplaces in managing human and hybrid human machine computing. Labor marketplaces offer many advantages that in combination allow human intelligence to be allocated across projects rapidly and efficiently and information to be transmitted effectively between market participants. Human computation comes with a set of challenges that are distinct from machine computation, including increased unsystematic error (e.g. mistakes) and systematic error (e.g. cognitive biases), both of which can be exacerbated when motivation is low, incentives are misaligned, and task requirements are poorly communicated. We provide specific guidance to how to ameliorate these issues through task design, workforce selection, data cleaning and aggregation.

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Keywords crowdfunding, crowdsourcing, human computation
ISBN 978-1-4614-8805-7
Persistent URL hdl.handle.net/1765/51293
Note This manuscript appeared as a chapter of the Handbook of Human Computation (Springer). Please cite: Chandler, J., Paolacci, G., & Mueller, P. (2013). Risks and rewards of crowdsourcing marketplaces. In Handbook of Human Computation (pp. 377-392). Springer New York.
Chandler, J, Paolacci, G, & Mueller, P. (2013). Risks and Rewards of Crowdsourcing Marketplaces. In Handbook of Human Computation (pp. 377–392). Retrieved from http://hdl.handle.net/1765/51293