🤖 AI Summary
Open-vocabulary multimodal sentiment recognition often struggles with ambiguous modality cues and dynamic contextual variations, leading to unreliable affective judgments. To address this challenge, this work proposes HyDRA, an architecture that formalizes hybrid evidential deductive reasoning as a learnable inference trajectory. HyDRA simulates multi-perspective evidence fusion through a Propose-Verify-Decide protocol and leverages reinforcement learning with a hierarchical reward mechanism to guide fine-grained affective state reconstruction. The approach not only enhances model robustness in ambiguous or conflicting scenarios but also yields interpretable and traceable diagnostic evidence paths. Experimental results demonstrate that HyDRA significantly outperforms strong baselines across multiple benchmarks, with particularly notable gains in challenging contextual settings.
📝 Abstract
Open-Vocabulary Multimodal Emotion Recognition (OV-MER) is inherently challenging due to the ambiguity of equivocal multimodal cues, which often stem from distinct unobserved situational dynamics. While Multimodal Large Language Models (MLLMs) offer extensive semantic coverage, their performance is often bottlenecked by premature commitment to dominant data priors, resulting in suboptimal heuristics that overlook crucial, complementary affective cues across modalities. We argue that effective affective reasoning requires more than surface-level association; it necessitates reconstructing nuanced emotional states by synthesizing multiple evidence-grounded rationales that reconcile these observations from diverse latent perspectives. We introduce HyDRA, a Hybrid-evidential Deductive Reasoning Architecture that formalizes inference as a Propose-Verify-Decide protocol. To internalize this abductive process, we employ reinforcement learning with hierarchical reward shaping, aligning the reasoning trajectories with final task performance to ensure they best reconcile the observed multimodal cues. Systematic evaluations validate our design choices, with HyDRA consistently outperforming strong baselines--especially in ambiguous or conflicting scenarios--while providing interpretable, diagnostic evidence traces.