A Difficulty in Trust Modelling

Muller, Tim

Abstract

There are various trust models, and no pair are the same. Why is there no consensus on what the best trust model is yet? In this paper, we prove some impossibility results, that suggests that no perfect trust model exists. We provide a general meta-model of trust models. A new concept, belief-consistence, is introduced. If a trust model is not belief-consistent, then it cannot model anyone's beliefs. We show that trust models without uncertainty can only be belief-consistent is an extremely simple case. Moreover, full trust models cannot be belief-consistent, even with uncertainty. Finally, we show how any discrepancies in belief can be blown up into arbitrary errors.

• Conference Name: 14th IFIP International Conference on Trust Management (IFIPTM 2023)
• Conference Location: Amsterdam, Netherlands
• Start Date: Oct 19, 2023
• End Date: Oct 20, 2023
• Acceptance Date: Sep 1, 2023
• Online Publication Date: Oct 20, 2023
• Publication Date: Oct 20, 2023
• Deposit Date: Feb 23, 2024
• Publicly Available Date: Feb 26, 2024
• Publisher: Springer
• Public URL: https://nottingham-repository.worktribe.com/output/25362141
• Related Public URLs: https://event.cwi.nl/ifiptm2023/