Trust and reputation in open multi-agent systems

Trust and reputation are central to effective interactions in open multi-agent systems (MAS) in which agents, that are owned by a variety of stakeholders, continuously enter and leave the system. This openness means existing trust and reputation models cannot readily be used since their performance suffers when there are various (unforseen) changes in the environment. To this end, this thesis develops and evaluates FIRE, a trust and reputation model that enables autonomous agents in open MAS to evaluate the trustworthiness of their peers and to select good partners for interactions. FIRE integrates four sources of trust information under the same framework in order to provide a comprehensive assessment of an agent’s likely performance in open systems. Specifically, FIRE incorporates interaction trust, role-based trust, witness reputation, and certified reputation, that models trust resulting from direct experiences, role-based relationships, witness reports, and third-party references, respectively, to provide trust metrics in most circumstances. A novel model of reporter credibility has also been integrated to enable FIRE to effectively deal with inaccurate reports (from witnesses and referees). Finally, adaptive techniques have been introduced, which make use of the information gained from monitoring the environment, to dynamically adjust a number of FIRE’s parameters according to the actual situation an agent finds itself in. In all cases, a systematic empirical analysis is undertaken to evaluate the effectiveness of FIRE in terms of the agent’s performance

GIDS: Global Interlinked Data Store

This paper introduces the Global Interlinked Data Store1 (GIDS), a technique to support the easy creation and retrieval of interlinked semantic data within a web-scale distributed network environment such as the World Wide Web (WWW). The GIDS enables the network to be treated as a data store without worrying about files, databases or other traditional data storage concerns. Data created on the network can be subsequently accessed and navigated by end users and software agents alike. The GIDS proposes a novel three-stage data storage process which enables the data to be stored in up to three contextually relevant locations to enhance subsequent retrieval opportunities. We believe that the capability offered by the GIDS will be of significant use to rapidly formed diverse coalitions who wish to communicate and exchange semantic data in a large network environment such as the WWW

The Cognitive Virtues of Dynamic Networks

For the most part, studies in the network science literature tend to focus on networks whose functional connectivity is largely invariant with respect to some episode of collective information processing. In the real world, however, networks with highly dynamic functional topologies tend to be the norm. In order to improve our understanding of the effect of dynamic networks on collective cognitive processing, we explored the problem-solving abilities of synthetic agents in dynamic networks, where the links between agents were progressively added throughout the problem-solving process. The results support the conclusion that (at least in some task contexts) dynamic networks contribute to a better profile of problem-solving performance compared to static networks (whose topologies are fixed throughout the course of information processing). Furthermore, the results suggest that constructive networks (like those used in the present study) strike a productive balance between autonomy and social influence. When agents are allowed to operate independently at the beginning of a problem-solving process, and then later allowed to communicate, the result is often a better profile of collective performance than if extensive communication had been permitted from the very outset of the problem-solving process. These results are relevant, we suggest, to a range of phenomena, such as groupthink, the common knowledge effect and production blocking, all of which have been observed in group problem-solving contexts

Supporting Distributed Coalition Planning with Semantic Wiki Technology

Contemporary and near-future military coalition environments present a number of challenges for military planning. Not only must military planners create plans against a backdrop of strict time constraints and uncertain information, they must also coordinate their planning efforts with other planning staff (often from different organizational, linguistic and cultural communities). This paper examines the potential for semantic wikis to support collaborative planning activities in the face of these challenges. Whilst we do not claim that semantic wikis could support all aspects of the collaborative planning process, we do suggest that semantic wikis can provide a highly configurable online editing environment which is likely to be of value in at least some coalition planning contexts. The strengths of semantic wikis include their support for distributed editing, their support for flexible forms of information presentation, and the opportunities they provide for new forms of inter-agent coordination. Their weaknesses include the absence of supportive plan editing interfaces and the limited support for the representation of highly expressive planning models. In the current paper, we discuss this profile of strengths and weaknesses, and we also discuss how a specific semantic wiki system, namely Semantic MediaWiki, could be used to support some aspects of collaborative planning

Crowdsourcing complex workflows under budget constraints

We consider the problem of task allocation in crowdsourcing systems with multiple complex workflows, each of which consists of a set of interdependent micro-tasks. We propose Budgeteer, an algorithm to solve this problem under a budget constraint. In particular, our algorithm first calculates an efficient way to allocate budget to each workflow. It then determines the number of inter-dependent micro-tasks and the price to pay for each task within each workflow, given the corresponding budget constraints. We empirically evaluate it on a well-known crowdsourcing-based text correction workflow using Amazon Mechanical Turk, and show that Budgeteer can achieve similar levels of accuracy to current benchmarks, but is on average 45% cheaper

Performance of export-oriented small and medium-sized manufacturing enterprises in Viet Nam

The study recommends the formulation of policies that support the development of business linkages and networking, and which promote subcontracting arrangements between small and large enterprises or between domestic firms and foreign investment enterprises. It is also necessary to support and facilitate the direct involvement of SMMEs in exporting or indirectly through large manufacturing enterprises.Export-oriented, SME,SMME, Viet Nam

Why Are Conversational Assistants Still Black Boxes? The Case For Transparency

Much has been written about privacy in the context of conversational and voice assistants. Yet, there have been remarkably few developments in terms of the actual privacy offered by these devices. But how much of this is due to the technical and design limitations of speech as an interaction modality? In this paper, we set out to reframe the discussion on why commercial conversational assistants do not offer meaningful privacy and transparency by demonstrating how they \emph{could}. By instrumenting the open-source voice assistant Mycroft to capture audit trails for data access, we demonstrate how such functionality could be integrated into big players in the sector like Alexa and Google Assistant. We show that this problem can be solved with existing technology and open standards and is thus fundamentally a business decision rather than a technical limitation.Comment: To appear in the Proceedings of the 2023 ACM conference on Conversational User Interfaces (CUI 23

PROV-JSONLD: a JSON and linked data representation for provenance

In this paper, we propose a representation for PROV in JSON-LD, the JSON format for Linked Data, called PROV-JSONLD. As a JSON-based format, this provenance representation can be readily consumed by Web applications currently supporting JSON. As a Linked Data format, at the same time, it also represents provenance data in RDF using the PROV ontology. Hence, it is suitable for usages in both the Web and the Semantic Web

STUDY ON THE PHOTOCATALYTIC DEGRADATION OF DICLOFENAC AND SULCOTRIONE IN SOME LAKE WATER SUBSTRATES IN HANOI

Joint Research on Environmental Science and Technology for the Eart