Trust on the Web: Some Web Science Research Challenges

Web Science is the interdisciplinary study of the World Wide Web as a first-order object in order to understand its relationship with the wider societies in which it is embedded, and in order to facilitate its future engineering as a beneficial object. In this paper, research issues and challenges relating to the vital topic of trust are reviewed, showing how the Web Science agenda requires trust to be addressed, and how addressing the challenges requires a range of disciplinary skills applied in an integrated manner

Trust Strategies for the Semantic Web

Everyone agrees on the importance of enabling trust on the SemanticWebto ensure more efficient agent interaction. Current research on trust seems to focus on developing computational models, semantic representations, inference techniques, etc. However, little attention has been given to the plausible trust strategies or tactics that an agent can follow when interacting with other agents on the Semantic Web. In this paper we identify five most common strategies of trust and discuss their envisaged costs and benefits. The aim is to provide some guidelines to help system developers appreciate the risks and gains involved with each trust strategy

TRULLO - local trust bootstrapping for ubiquitous devices

Handheld devices have become sufficiently powerful that it is easy to create, disseminate, and access digital content (e.g., photos, videos) using them. The volume of such content is growing rapidly and, from the perspective of each user, selecting relevant content is key. To this end, each user may run a trust model - a software agent that keeps track of who disseminates content that its user finds relevant. This agent does so by assigning an initial trust value to each producer for a specific category (context); then, whenever it receives new content, the agent rates the content and accordingly updates its trust value for the producer in the content category. However, a problem with such an approach is that, as the number of content categories increases, so does the number of trust values to be initially set. This paper focuses on how to effectively set initial trust values. The most sophisticated of the current solutions employ predefined context ontologies, using which initial trust in a given context is set based on that already held in similar contexts. However, universally accepted (and time invariant) ontologies are rarely found in practice. For this reason, we propose a mechanism called TRULLO (TRUst bootstrapping by Latently Lifting cOntext) that assigns initial trust values based only on local information (on the ratings of its user’s past experiences) and that, as such, does not rely on third-party recommendations. We evaluate the effectiveness of TRULLO by simulating its use in an informal antique market setting. We also evaluate the computational cost of a J2ME implementation of TRULLO on a mobile phone

A Framework for Trusted Services

An existing challenge when selecting services to be used in a service- based system is to be able to distinguish between good and bad services. In this paper we present a trust-based service selection framework. The framework uses a trust model that calculates the level of trust a user may have with a service based on past experience of the user with the service and feedback about the service received from other users. The model takes into account different levels of trust among users, different relationships between users, and different levels of importance that a user may have for certain quality aspects of a service. A prototype tool has been implemented to illustrate and evaluate the work. The trust model has been evaluated in terms of its capacity to adjust itself due to changes in user ratings and its robustness

Trust-Based Service Selection

Service Oriented Architecture (SOA) is an architectural style that builds enterprise solutions based on services. In SOA, the lack of trust between different parties affects the adoption of such architecture. Trust is as significant a factor for successful online interactions as it is in real life communities, and consequently, it is an important factor that is used as a criterion for service selection. In the context of online services and SOA, the literature shows that the field of trust is not mature. Trust definition and the consideration of the essentials of trust aspects do not reflect the true nature of trust online. This thesis proposes a trust-based service selection solution, which requires establishing trust for services and supporting service selection based on trust. This work considers building trust for service providers besides rating services, an area that is neglected in the literature. This work follows progressive steps to arrive at a solution. First, this work develops a trust definition and identifies trust principles, which cover different aspects of trust. Next, SOA is extended to build a trust-based SOA that supports trust-based service selection. In particular, a new component, the trust mediator, which is responsible for trust establishment is added to the architecture. Accordingly, a trust mediator framework is built according to the trust definition and principles to identify its main components. Subsequently, this work identifies the trust information, or metrics, for services and service providers. Accordingly, trust models are built to evaluate trust rates for the applicable metrics, services, and service providers. Moreover, this work addresses the trust bootstrapping challenge. The proposed trust bootstrapping approach addresses different challenges in the literature such as whitewashing and cold start. This approach is implemented through experiments, evaluations, and scenarios