Minimizing hitting time between disparate groups with shortcut edges
2023 (English)In: KDD 2023: Proceedings of the 29th ACM SIGKDD Conference on Knowledge Discovery and Data Mining, Association for Computing Machinery (ACM) , 2023, p. 1-10Conference paper, Published paper (Refereed)
Abstract [en]
Structural bias or segregation of networks refers to situations where two or more disparate groups are present in the network, so that the groups are highly connected internally, but loosely connected to each other. Examples include polarized communities in social networks, antagonistic content in video-sharing or news-feed platforms, etc. In many cases it is of interest to increase the connectivity of disparate groups so as to, e.g., minimize social friction, or expose individuals to diverse viewpoints. A commonly-used mechanism for increasing the network connectivity is to add edge shortcuts between pairs of nodes. In many applications of interest, edge shortcuts typically translate to recommendations, e.g., what video to watch, or what news article to read next. The problem of reducing structural bias or segregation via edge shortcuts has recently been studied in the literature, and random walks have been an essential tool for modeling navigation and connectivity in the underlying networks. Existing methods, however, either do not offer approximation guarantees, or engineer the objective so that it satisfies certain desirable properties that simplify the optimization task. In this paper we address the problem of adding a given number of shortcut edges in the network so as to directly minimize the average hitting time and the maximum hitting time between two disparate groups. The objectives we study are more natural than objectives considered earlier in the literature (e.g., maximizing hitting-time reduction) and the optimization task is significantly more challenging. Our algorithm for minimizing average hitting time is a greedy bicriteria that relies on supermodularity. In contrast, maximum hitting time is not supermodular. Despite, we develop an approximation algorithm for that objective as well, by leveraging connections with average hitting time and the asymmetric k-center problem.
Place, publisher, year, edition, pages
Association for Computing Machinery (ACM) , 2023. p. 1-10
Keywords [en]
edge augmentation, polarization, random walks, social networks
National Category
Computer Sciences
Identifiers
URN: urn:nbn:se:kth:diva-337891DOI: 10.1145/3580305.3599434Scopus ID: 2-s2.0-85171335636OAI: oai:DiVA.org:kth-337891DiVA, id: diva2:1803827
Conference
29th ACM SIGKDD Conference on Knowledge Discovery and Data Mining, KDD 2023, Long Beach, United States of America, Aug 6 2023 - Aug 10 2023
Note
Part of ISBN 9798400701030
QC 20231010
2023-10-102023-10-102024-12-03Bibliographically approved