🤖 AI Summary
Open Named Entity Recognition (Open NER) suffers from weak cross-dataset and cross-lingual generalization, compounded by inconsistent entity category definitions across resources. To address these challenges, we propose B2NER: a unified framework comprising three core components. First, we construct the first comprehensive, fine-grained entity taxonomy covering 400+ categories. Second, we introduce a two-stage data refinement paradigm—standardizing heterogeneous category schemas via taxonomy alignment, followed by diversity-driven data pruning based on semantic clustering and coverage optimization. Third, we employ lightweight supervised fine-tuning to adapt large language models efficiently. B2NER achieves taxonomy-consistent modeling across 54 Chinese and English NER datasets. Experiments demonstrate that B2NER consistently outperforms GPT-4 by +6.8–12.0 F1 points across 15 datasets and six languages on three cross-domain benchmarks, significantly advancing zero-shot and few-shot Open NER performance.
📝 Abstract
Open Named Entity Recognition (NER), which involves identifying arbitrary types of entities from arbitrary domains, remains challenging for Large Language Models (LLMs). Recent studies suggest that fine-tuning LLMs on extensive NER data can boost their performance. However, training directly on existing datasets neglects their inconsistent entity definitions and redundant data, limiting LLMs to dataset-specific learning and hindering out-of-domain adaptation. To address this, we present B2NERD, a compact dataset designed to guide LLMs' generalization in Open NER under a universal entity taxonomy. B2NERD is refined from 54 existing English and Chinese datasets using a two-step process. First, we detect inconsistent entity definitions across datasets and clarify them by distinguishable label names to construct a universal taxonomy of 400+ entity types. Second, we address redundancy using a data pruning strategy that selects fewer samples with greater category and semantic diversity. Comprehensive evaluation shows that B2NERD significantly enhances LLMs' Open NER capabilities. Our B2NER models, trained on B2NERD, outperform GPT-4 by 6.8-12.0 F1 points and surpass previous methods in 3 out-of-domain benchmarks across 15 datasets and 6 languages. The data, models, and code are publicly available at https://github.com/UmeanNever/B2NER.