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How to trust a few among many


The presence of numerous and disparate information sources available to support decision-making calls for efficient methods of harnessing their potential. Information sources may be unreliable, and misleading reports can affect decisions. Existing trust and reputation mechanisms typically rely on reports from as many sources as possible to mitigate the influence of misleading reports on decisions. In the real world, however, it is often the case that querying information sources can be costly in terms of energy, bandwidth, delay overheads, and other constraints. We present a model of source selection and fusion in resource-constrained environments, where there is uncertainty regarding the trustworthiness of sources. We exploit diversity among sources to stratify them into homogeneous subgroups to both minimise redundant sampling and mitigate the effect of certain biases. Through controlled experiments, we demonstrate that a diversity-based approach is robust to biases introduced due to dependencies among source reports, performs significantly better than existing approaches when sampling budget is limited and equally as good with an unlimited budget.

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  1. See: for how Twitter was used to spread false rumours during the England riots of 2011.

  2. This is consistent with most real-world economic settings [11].

  3. We use the M5 implementation of Weka [14], a popular open-source machine learning toolkit written in Java

  4. The M5 algorithm can accommodate other feature types including qualitative. As well as this, different metrics exist for computing the distance between features of other kinds [17].


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Dr. Şensoy thanks to the U.S. Army Research Laboratory for its support under grant W911NF-14-1-0199 and The Scientific and Technological Research Council of Turkey (TUBITAK) for its support under grant 113E238.

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Correspondence to Murat Şensoy.

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Etuk, A., Norman, T.J., Şensoy, M. et al. How to trust a few among many. Auton Agent Multi-Agent Syst 31, 531–560 (2017).

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