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arXiv · 2602.16144

Missing-by-Design: Certifiable Modality Deletion for Revocable Multimodal Sentiment Analysis

Rong Fu·Ziming Wang·Chunlei Meng·Jiekai Wu·Kangan Qian·Hao Zhang·Simon Fong
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Abstract

As multimodal systems increasingly process sensitive personal data, the ability to selectively revoke specific data modalities has become a critical requirement for privacy compliance and user autonomy. We present Missing-by-Design (MBD), a unified framework for revocable multimodal sentiment analysis that combines structured representation learning with a certifiable parameter-modification pipeline. Revocability is critical in privacy-sensitive applications where users or regulators may request removal of modality-specific information. MBD learns property-aware embeddings and employs generator-based reconstruction to recover missing channels while preserving task-relevant signals. For deletion requests, the framework applies saliency-driven candidate selection and a calibrated Gaussian update to produce a machine-verifiable Modality Deletion Certificate. Experiments on benchmark datasets show that MBD achieves strong predictive performance under incomplete inputs and delivers a practical privacy-utility trade-off, positioning surgical unlearning as an efficient alternative to full retraining.

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Rong Fu, Ziming Wang, Chunlei Meng, Jiekai Wu, Kangan Qian, Hao Zhang, Simon Fong. 2026-08-03. Missing-by-Design: Certifiable Modality Deletion for Revocable Multimodal Sentiment Analysis. https://arxiv.org/abs/2602.16144

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