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SNBot: Modeling Self–Neighborhood Representation Discrepancy for Social Bot Detection

Jul 2026 · Annual International ACM SIGIR Conference on Research and Development in Information Retrieval · pp. 1130-1140 · 0 citations · 48 references
Computer Science

TL;DR

SNBot is proposed, a novel social bot detection framework that explicitly models the discrepancy between node self-representations and their neighborhood embeddings and consistently outperforms state-of-the-art methods.

Abstract

The proliferation of social bots poses a persistent threat to online social platforms, making accurate and efficient detection increasingly critical. Although recent graph-based methods have achieved notable progress by modeling user interactions, many of them implicitly assume neighborhood consistency and degrade in sparse, directed, and heterophilic social graphs, where a user's neighborhood may poorly reflect its own attributes. In this work, we propose SNBot, a novel social bot detection framework that explicitly models the discrepancy between node self-representations and their neighborhood embeddings. SNBot first learns unified self-representations from multi-modal user attributes through a lightweight type-aware encoding scheme. It then performs message passing on an augmented directed graph using a bidirectional aggregation mechanism, which separately captures incoming and outgoing interactions to better characterize asymmetric behaviors. By preserving and exploiting self–neighborhood representation discrepancies rather than over-smoothing them, SNBot produces more discriminative node representations. Extensive experiments on multiple real-world benchmark datasets demonstrate that SNBot consistently outperforms state-of-the-art methods.

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