User- and Community-Adaptive Rewards Mechanism for Sustainable Online Community

Abstract. Abundance of user contributions does not necessarily indicate sustainability of an online community. On the contrary, excessive contributions in the systems may result in “information overload ” and user withdrawal. We propose an adaptive rewards mechanism aiming to restrict the quantity of the contributions, elicit contributions with higher quality and simultaneously inhibit inferior ones. The mechanism adapts to the users preferences with respect to types of contributions and to the current needs of the community depending on the time and the number of existing contributions.

Use multiple modeling approaches to study sustained online communities

In recent years, extensive studies of many interesting aspects of online community dynamics promoted a better understanding of this area. One of the most challenging problems facing builders of online communities is the design of incentive mechanisms that can ensure user participation. However, running online community experiments in the real world is expensive, and requires a great deal of motivation from users. In this thesis two major approaches are explored: system dynamics modeling and agent-based modeling, to simulate the overall behaviours of participants in online communities. Although these models are developed by using two different methodologies, both of them can provide insights into the user motivation process, incentive mechanism evaluation and community development. The target online community for my study is called Comtella, which is used in several senior Computer Science classes in the Department of Computer Science, University of Saskatchewan. Simulation models for the Comtella online community have been developed and the simulation results are useful to provide future directions for incentive mechanism improvement

Principles for Fairness and Efficiency in Enhancing Environmental Services in Asia: Payments, Compensation, or Co-Investment?

The term payments for environmental services (PES) has rapidly gained popularity, with its focus on market-based mechanisms for enhancing environmental services (ES). Current use of the term, however, covers a broad spectrum of interactions between ES suppliers and beneficiaries. A broader class of mechanisms pursues ES enhancement through compensation or rewards. Such mechanisms can be analyzed on the basis of how they meet four conditions: realistic, conditional, voluntary, and pro-poor. Based on our action research in Asia in the Rewarding Upland Poor for Environmental Services (RUPES) program since 2002, we examine three paradigms: commoditized ES (CES), compensation for opportunities skipped (COS), and co-investment in (environmental) stewardship (CIS). Among the RUPES action research sites, there are several examples of CIS with a focus on assets (natural + human + social capital) that can be expected to provide future flows of ES. CES, equivalent to a strict definition of PES, may represent an abstraction rather than a current reality. COS is a challenge when the legality of opportunities to reduce ES is contested. The primary difference between CES, COS, and CIS is the way in which conditionality is achieved, with additional variation in the scale (individual, household, or community) at which the voluntary principle takes shape. CIS approaches have the greatest opportunity to be pro-poor, as both CES and COS presuppose property rights that the rural poor often do not have. CIS requires and reinforces trust building after initial conflicts over the consequences of resource use on ES have been clarified and a realistic joint appraisal is obtained. CIS will often be part of a multiscale approach to the regeneration and survival of natural capital, alongside respect and appreciation for the guardians and stewards of landscapes

User motivational mechanism for building sustained online communities

The proliferation of online communities on the Internet nowadays may lead people to the conclusion that the development of custom-made communities for particular purpose is straightforward. Unfortunately, this is not the case. Although software providing basic community infrastructure is readily available, it is not enough to ensure that the online community will “take off” and become sustained. Most online communities suffer from the scarcity of the user participation in their initial phase. To address the problem, this thesis proposes a motivational mechanism to encourage user participation. The main idea is to introduce a set of hierarchical memberships into online communities and reward active users with better quality of services. The mechanism has been applied in a small-scale online community called Comtella and evaluated. The results showed that, although the mechanism was able to motivate users to participate more actively and make more contributions, it led to a deteriorating quality of user contributions, catalyzed “information overload” in the community and resulted in a decrease in user participation towards the end of the study. Therefore, to regulate the quality and the quantity of user contributions and ensure a sustainable level of user participation in the online community, the proposed mechanism was improved so that it was able to adapt the rewards for particular forms of participation for individual users depending on their reputation and the current need of the community, thereby influencing their actions of contributing. The improved mechanism was also implemented and evaluated in the Comtella system. The results of evaluation showed that the mechanism can guarantee stable and active user participation and lower the level of information overload in the online community and therefore it can enhance the sustainability of the community

Decentralized Adaptive Helper Selection in Multi-channel P2P Streaming Systems

In Peer-to-Peer (P2P) multichannel live streaming, helper peers with surplus bandwidth resources act as micro-servers to compensate the server deficiencies in balancing the resources between different channel overlays. With deployment of helper level between server and peers, optimizing the user/helper topology becomes a challenging task since applying well-known reciprocity-based choking algorithms is impossible due to the one-directional nature of video streaming from helpers to users. Because of selfish behavior of peers and lack of central authority among them, selection of helpers requires coordination. In this paper, we design a distributed online helper selection mechanism which is adaptable to supply and demand pattern of various video channels. Our solution for strategic peers' exploitation from the shared resources of helpers is to guarantee the convergence to correlated equilibria (CE) among the helper selection strategies. Online convergence to the set of CE is achieved through the regret-tracking algorithm which tracks the equilibrium in the presence of stochastic dynamics of helpers' bandwidth. The resulting CE can help us select proper cooperation policies. Simulation results demonstrate that our algorithm achieves good convergence, load distribution on helpers and sustainable streaming rates for peers

Twenty Years of Working Towards a Sustainable Southeast Asia: 1993 -- 2013

The Southeast Asia program first set about testing hypotheses applicable to each of the three ecosystem zones. On the forest margins, the hypothesis was that complex agroforests provided a superior alternative for small-scale farmers to either food-crop systems or monocultural plantations of perennials. As an alternative to slash and burn, complex agroforests increased production sustainability, increased biodiversity, reduced production risks and increased returns to labour compared to continuous food crops or monocultural plantations. The second hypothesis stated that rehabilitating Imperata grasslands with small-scale agroforestry systems would be superior to plantation reforestation in terms of production, equitability and participation. For hilly farmlands, the team hypothesised that there were several pathways to sustainable farming. Among these, contour hedgerow systems initiated through natural vegetative strips provided distinct advantages as a superior, least-cost foundation upon which to build agroforestry-based, conservation farming

There's a monster in my kitchen: using aversive feedback to motivate behaviour change

In this paper we argue that “persuasive technologies,” developed to motivate behaviour change in users, have so far failed to exploit the established body of empirical research within behavioural science. We propose that persuasive technologies may benefit from both adapting to individual preferences, and a constructive use of aversive, in addition to appetitive, feedback. We detail an example application that demonstrates how this approach can be incorporated into an application designed to train users to adopt more environmentally friendly behaviours in their domestic kitchens

Collaborative information finding in smaller communities: The case of research talks

Social navigation and social tagging technologies enable user communities to assemble the collective wisdom, and use it to help community members in finding the right information. However, it takes a significantly-sized community to make a social system truly useful. The question addressed in this paper is whether collaborative information finding is feasible in the context of smaller communities. To answer this question, we developed two social systems specifically focused on smaller communities - CoMeT and Conference Navigator II - and explored several techniques to increase the volume of user contributions. This paper reviews the explored techniques and presents empirical evidence that demonstrate their effectiveness. © 2010 ICST