Indirect Trust is Simple to Establish

Authors: Elham Parhizkar, Mohammad Hossein Nikravan, Sandra Zilles

IJCAI 2019 | Conference PDF | Archive PDF | Plain Text | LLM Run Details

Reproducibility Variable Result LLM Response
Research Type Experimental We evaluate existing state-of-the-art methods for computing indirect trust in numerous simulations, demonstrating that the best ones tend to be of prohibitively large complexity. We propose a new and easy to implement method for computing indirect trust, based on a simple prediction with expert advice strategy as is often used in online learning. This method either competes with or outperforms all tested systems in the vast majority of the settings we simulated, while scaling substantially better. Our results demonstrate that existing systems for computing indirect trust are overly complex; the problem can be solved much more efficiently than the literature suggests.
Researcher Affiliation Academia Elham Parhizkar , Mohammad Hossein Nikravan and Sandra Zilles Department of Computer Science, University of Regina, Canada e.parhizkarabyaneh@gmail.com, nikravam@uregina.ca, zilles@cs.uregina.ca
Pseudocode Yes Algorithm 1 The ITEA Algorithm
Open Source Code No The paper does not include any explicit statements about releasing source code, nor does it provide a link to a code repository.
Open Datasets No The paper describes a simulated environment and how data is generated within that simulation ("The trustworthiness value of each individual trustee is sampled uniformly at random... Each reported result is the average over 100 such sampled trustee combinations.") rather than using a pre-existing, publicly available dataset with a direct access link or formal citation.
Dataset Splits No The paper describes its simulation setup and evaluation metrics (e.g., "after S successful interactions, the ratio... was recorded") but does not specify traditional training, validation, and test dataset splits with percentages or sample counts.
Hardware Specification Yes We measured CPU time on a Mac Book Pro/2.3 GHz Intel Core i7 for various settings.
Software Dependencies No The paper mentions specific methods and models like "Beta Reputation System (BRS)" and "DP-Dirichlet model", and a "squared-error loss" function, but it does not specify software dependencies with version numbers (e.g., Python 3.x, PyTorch 1.x).
Experiment Setup Yes ITEA requires a loss function and a learning rate. As loss function, we chose squared-error loss. As mentioned before, the learning rate η = p 8 ln(K)/T yields good guarantees, where K is the number of advisers and T the number of rounds of interaction with the trustee whose trustworthiness is being estimated. In our simulations, K = 100 and T is not known in advance, so that we replaced T by the total number of interactions (when measuring MAE) or the target number of positive interactions (when measuring RFU). ... Initialization: wk,0 = 1 K , 1 k K