Collective intelligence can arise in groups of individuals and is not just something that arises inside individual brains . A group of individuals (such as families, companies, and armies) sometimes behaves collectively in ways that seem intelligent, which is called “collective intelligence”. Malone et al.  define this as “groups of individuals acting collectively in ways that seem intelligent”.
Different disciplines of science such as economics, law, social psychology and political science, which investigate the behavior of groups of individuals, study collective intelligence only when there is a focus on overall collective behavior . For instance, investigating how individuals make economic choices or how their opinions and views are determined would not be the focus of collective intelligence. However, investigating how various controlling strategies in markets cause less or more intelligent behavior by the markets as a whole would be taken into consideration. Similarly, investigating how different organizational designs in a company cause better or worse performance by the company as a whole would also be taken into consideration by collective intelligence .
Joined groups of people and machines, which collectively perform intelligent things, is a new kind of collective intelligence. For example, within the last ten years, millions of people and computers authored the most comprehensive encyclopedia (Wikipedia), mainly by cooperation of volunteers and no unified control. And in more domains, surprisingly broad groups of people and computers are doing interesting tasks from solving engineering problems, to composing and editing documents, to predicting presidential elections.
Crowd sourcing, for instance, is a special case of collective intelligence, where a third party (called the requestor) with some internal objective requests a group of individuals (called workers) to perform a task in service of that objective . The objective of the requestor may be indicated in the form of a utility function to be maximized. For example, a requestor might wish to fund a project or venture by raising monetary contributions from two or more people by using a web service, which is called “Crowd-Funding”.
Finally, a key factor to be considered is that participation and contribution in crowd sourcing and in general for collective intelligence is voluntary — contributors may decide to take part or not. It should also be noted that many crowd-based activities fail, either immediately or eventually, because of very few contributions. Moreover, having decided to participate does not necessarily mean that contributors will put effort into their contributions. Therefore, a mechanism to moderate and motivate high quality of contributions is an essential requirement. Subsequently, there are still many challenges and issues to be solved in order to make strength of the collective intelligence (and in particular crowd sourcing) exploitable in different application domains.
An interesting conference on this topic is organized by the University of Michigan. Further information below. http://sites.lsa.umich.edu/collectiveintelligence/
This article is an abstract from the references below, in case of extended interest we recommend reading the following publications:
 Malone, T. W., and Bernstein M. S. The Collective Intelligence Handbook. MIT Press 2014
 Malone, T. W., Laubacher, R. & Dellarocas, C. N. (2009). Harnessing Crowds: Mapping the Genome of Collective Intelligence. MIT Center for Collective Intelligence Working
 Bigham J.P, Bernstein M. S., and Adar E, Human-Computer Interaction and Collective Intelligence Chapter of The Collective Intelligence Handbook. MIT Press 2014
Mag. Matthias Ortner
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