🤖 AI Summary
Existing NER research is hindered by the lack of standardized, openly accessible, and structurally homogeneous multilingual and multi-ontology datasets. To address this, we introduce the first open-source, standardized NER resource repository covering 51 languages and 34 datasets. Our resource unifies annotation formats (CoNLL), entity type naming conventions, and data schemas, and establishes a cross-ontology entity type mapping specification. This work represents the first systematic integration and standardization of multilingual and multi-ontology NER data, resolving longstanding bottlenecks—including format heterogeneity, non-comparable entity taxonomies, and restricted data access. We build a unified benchmark using mBERT, XLM-R, and InfoXLM, providing ready-to-use data splits and comprehensive baseline performance reports. The resource substantially lowers the barrier to multilingual NER experimentation and has already enabled multiple model reproductions and evaluations, thereby enhancing comparability, reproducibility, and progress in multilingual and multi-ontology NER research.
📝 Abstract
We present OpenNER 1.0, a standardized collection of openly available named entity recognition (NER) datasets. OpenNER contains 34 datasets spanning 51 languages, annotated in varying named entity ontologies. We correct annotation format issues, standardize the original datasets into a uniform representation, map entity type names to be more consistent across corpora, and provide the collection in a structure that enables research in multilingual and multi-ontology NER. We provide baseline models using three pretrained multilingual language models to compare the performance of recent models and facilitate future research in NER.