Fairness Emergence in Reputation Systems

Reputation systems have been used to support users in making decisions under uncertainty or risk that is due to the autonomous behavior of others. Research results support the conclusion that reputation systems can protect against exploitation by unfair users, and that they have an impact on the prices and income of users. This observation leads to another question: can reputation systems be used to assure or increase the fairness of resource distribution? This question has a high relevance in social situations where, due to the absence of established authorities or institutions, agents need to rely on mutual trust relations in order to increase fairness of distribution. This question can be formulated as a hypothesis: in reputation (or trust management) systems, fairness should be an emergent property. The notion of fairness can be precisely defined and investigated based on the theory of equity. In this paper, we investigate the Fairness Emergence hypothesis in reputation systems and prove that , under certain conditions, the hypothesis is valid for open and closed systems, even in unstable system states and in the presence of adversaries. Moreover, we investigate the sensitivity of Fairness Emergence and show that an improvement of the reputation system strengthens the emergence of fairness. Our results are confirmed using a trace-driven simulation from a large Internet auction site.Trust, Simulation, Fairness, Equity, Emergence, Reputation System

Looking for big money in the grey zone. Simulation of High Yield Investment Programs strategies

High Yield Investment Programs (HYIPs) are online versions of a Ponzi scheme, a fraud that offers extremely high interest rates to attract investors – and pays them up to the moment when HYIP owner decides to run away with the money accumulated in the account. This article presents a simulation focused on the connections between investments in appealing websites, advertising, and runaway strategies to explore and describe one of the grey zone areas. The model is based to a large extent on real-life data acquired from HYIP monitors. In this paper, we have proven that advertising and layout have a great impact on an HYIP’s balance. Moreover, most HYIPs are capable of gaining similar balance; however, there are also conservative strategies that significantly reduce profits

The harm in conflating aging with accessibility

Including older adults as full stakeholders in digital society. </p

Influence of consumer reviews on online purchasing decisions in older and younger adults

We investigated how product attributes, average consumer ratings, and single affect-rich positive or negative consumer reviews influenced hypothetical online purchasing decisions of younger and older adults. In line with previous research, we found that younger adults used all three types of information: they clearly preferred products with better attributes and with higher average consumer ratings. If making a choice was difficult because it involved trade-offs between product attributes, most younger adults chose the higher-rated product. The preference for the higher-rated product, however, could be overridden by a single affect-rich negative or positive review. Older adults were strongly influenced by a single affect-rich negative review and also took into consideration product attributes; however, they did not take into account average consumer ratings or single affect-rich positive reviews. These results suggest that older adults do not consider aggregated consumer information and positive reviews focusing on positive experiences with the product, but are easily swayed by reviews reporting negative experiences

Multilevel Modeling of Distributed Denial of Service Attacks in Wireless Sensor Networks

The growing popularity of wireless sensor networks increases the risk of security attacks. One of the most common and dangerous types of attack that takes place these days in any electronic society is a distributed denial of service attack. Due to the resource constraint nature of mobile sensors, DDoS attacks have become a major threat to its stability. In this paper, we established a model of a structural health monitoring network, being disturbed by one of the most common types of DDoS attacks, the flooding attack. Through a set of simulations, we explore the scope of flood-based DDoS attack problem, assessing the performance and the lifetime of the network under the attack condition. To conduct our research, we utilized the Quality of Protection Modeling Language. With the proposed approach, it was possible to examine numerous network configurations, parameters, attack options, and scenarios. The results of the carefully performed multilevel analysis allowed us to identify a new kind of DDoS attack, the delayed distributed denial of service, by the authors, referred to as DDDoS attack. Multilevel approach to DDoS attack analysis confirmed that, examining endangered environments, it is significant to take into account many characteristics at once, just to not overlook any important aspect