Echoes within the Reasoning: Stealthy and Effective Watermarking via Chain of Thought

Large Language Models with Chain-of-Thought reasoning capabilities represent valuable intellectual property, yet existing black-box watermarking methods often trade robustness for reasoning fidelity by perturbing final answers or relying on fragile trigger patterns. We propose BiCoT, a watermarking framework that embeds ownership signals into the internal geometry of reasoning traces by aligning high-saliency structural anchors with a private signature subspace while regularizing ordinary control tokens to preserve semantic capacity. This design couples the watermark with reasoning-relevant representations, making removal difficult without disrupting the features that support coherent reasoning. To enable verification under model theft and representation drift, we introduce Robust Subspace Registration (RSR), a Top- logprob-based black-box verifier that uses sentinel tokens to calibrate systematic shifts in the output distribution. Experiments show that BiCoT preserves reasoning fidelity across diverse complex reasoning tasks while achieving robust detection under fine-tuning, quantization, model-level perturbations, and adaptive output-level attacks across in-domain and out-of-distribution settings.

MUFM: A Mamba-Enhanced Feedback Model for Micro Video Popularity Prediction

The surge in micro-videos is transforming the concept of popularity. As researchers delve into vast multi-modal datasets, there is a growing interest in understanding the origins of this popularity and the forces driving its rapid expansion. Recent studies suggest that the virality of short videos is not only tied to their inherent multi-modal content but is also heavily influenced by the strength of platform recommendations driven by audience feedback. In this paper, we introduce a framework for capturing long-term dependencies in user feedback and dynamic event interactions, based on the Mamba Hawkes process. Our experiments on the large-scale open-source multi-modal dataset show that our model significantly outperforms state-of-the-art approaches across various metrics by 23.2%. We believe our model's capability to map the relationships within user feedback behavior sequences will not only contribute to the evolution of next-generation recommendation algorithms and platform applications but also enhance our understanding of micro video dissemination and its broader societal impact.