While the literature highlights a wide variety of potential citizen science project outcomes, no prior studies have systematically assessed performance against a comprehensive set of criteria. Our study is the first to propose a novel framework for assessing citizen science projects against multiple dimensions of success. We apply this framework to a sample of projects forming part of the online Zooniverse platform and position these projects against a 'success matrix' measuring both contribution to science and public engagement levels relative to others in the sample. Our results indicate that better performing projects tend to be those which are more established, as well as those in the area of astronomy. Implications for citizen science practitioners include the need to consider the impact of core competencies on project performance, as well as the importance of relationships between the central organisation and science teams.

We investigate the development of scientific content knowledge of volunteers participating in online citizen science projects in the Zooniverse (http://www.zooniverse.org). We use econometric methods to test how measures of project participation relate to success in a science quiz, controlling for factors known to correlate with scientific knowledge. Citizen scientists believe they are learning about both the content and processes of science through their participation. We don't directly test the latter, but we find evidence to support the former — that more actively engaged participants perform better in a project-specific science knowledge quiz, even after controlling for their general science knowledge. We interpret this as evidence of learning of science content inspired by participation in online citizen science.

LSE has developed LSE Research Online so that users may access research output of the School. Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in LSE Research Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain. You may freely distribute the URL (http://eprints.lse.ac.uk) of the LSE Research Online website. This document is the author's final accepted version of the journal article. There may be differences between this version and the published version. You are advised to consult the publisher's version if you wish to cite from it. Using survey data from a representative sample of contributors, this study investigates motivations to volunteer across a sample of five such online projects using the Volunteer

Purpose -This paper examines intrinsic forms of motivation and particular incidents of play, socialisation, fun and amusement on an online crowdsourced citizen science platform. The paper also investigates gamised activity (Greenhill et al., 2014) as a form of intrinsic motivation adding a sense of play to work and tasks (Xu et al., 2012). These concepts are explored through close scrutiny of the online citizen science platform Zooniverse.org. Design/methodology/approach -Qualitative techniques with an interpretivist approach are used to analyse online content found within citizen science platforms, related forums and social media by examining incidents of play, socialisation, fun and amusement to investigate how these aspects are applied as a form of user motivation. Findings -We find that when users classify crowdsourced tasks voluntarily It does not matter how users are classifying as long as it is accurately. However, what does matter is why they are doing it particularly because of the complex processes that builds relationships between users and the platform. We present a conceptual model to enable deeper understandings of how forms of social interaction and play are motivating users contributing to citizen science project to participate in the online processes. Practical implications -The findings of this paper provide practical implications for how citizen science, and also other crowdsourcing platforms, can engage with notions of play and gamification to motivate participation. Originality/value -Using detailed examples of online content, we reveal how participants of the Zooniverse.org demonstrate aspects of 'gamised' behaviour. We argue that the exploration of gaming as well as play provides evidence that contributing to citizen science projects can be both utilitarian and hedonic.

The views expressed in this publication are those of the authors and do not necessarily reflect the views and policies of the Asian Development Bank (ADB) or its Board of Governors or the governments they represent.ADB does not guarantee the accuracy of the data included in this publication and accepts no responsibility for any consequence of their use. The mention of specific companies or products of manufacturers does not imply that they are endorsed or recommended by ADB in preference to others of a similar nature that are not mentioned.By making any designation of or reference to a particular territory or geographic area, or by using the term "country" in this document, ADB does not intend to make any judgments as to the legal or other status of any territory or area.