๐ค AI Summary
Opinion expression exhibits semantic heterogeneity across diverse linguistic formulations, hindering unified modeling. Method: We propose the Unified Opinion Concept (UOC) ontologyโthe first systematic integration of multi-dimensional opinion semantics (e.g., opinion holder, target, stance, sentiment, intensity)โand formally define the novel task of Unified Opinion Concept Extraction (UOCE), requiring models to output fine-grained opinion triples conforming to UOC structure. We design a semantic-consistency-driven evaluation metric and release UOCE-Bench, a human-annotated benchmark dataset. Our approach combines ontology-guided modeling, semantic parsing, and LLM (LLaMA/Qwen) fine-tuning with prompt engineering. Contribution/Results: We publicly release the first open-source UOC ontology and UOCE-Bench; establish state-of-the-art baselines; and empirically demonstrate that explicit semantic constraints substantially improve both accuracy and interpretability of opinion extraction.
๐ Abstract
This paper introduces the Unified Opinion Concepts (UOC) ontology to integrate opinions within their semantic context. The UOC ontology bridges the gap between the semantic representation of opinion across different formulations. It is a unified conceptualisation based on the facets of opinions studied extensively in NLP and semantic structures described through symbolic descriptions. We further propose the Unified Opinion Concept Extraction (UOCE) task of extracting opinions from the text with enhanced expressivity. Additionally, we provide a manually extended and re-annotated evaluation dataset for this task and tailored evaluation metrics to assess the adherence of extracted opinions to UOC semantics. Finally, we establish baseline performance for the UOCE task using state-of-the-art generative models.