Paper Overview
Research Area: Machine Learning Authors: Hamed Babaei Giglou, Sören Auer, Peio Popov Published: 2025-09-01 arXiv: 2509.00145
Abstract
Ontology alignment (OA) has evolved through several methodological paradigms, ranging from lexical and structural aligners to knowledge graph embedding (KGE) models and, more recently, Large Language Model (LLM)-based approaches. Although modern OA frameworks provide unified ecosystems for deploying these heterogeneous aligners, mechanisms for systematically reconciling their complementary and sometimes conflicting predictions remain relatively underexplored.
The authors present OntoAligner-Ensemble, a modular and aligner-agnostic framework that combines candidate correspondences through a configurable two-stage process comprising voting-based fusion strategies followed by post-fusion selection policies. The framework supports any aligner implemented within OntoAligner that produces candidate correspondences, enabling diverse alignment paradigms to be integrated through a unified decision process.
Experimental Setup
To demonstrate effectiveness, the framework was instantiated with representative aligners:
- Lightweight string-based aligners
- KGE-based aligners
- Retrieval-augmented generation aligners powered by open-source and API-driven LLMs
- Ensemble fusion consistently improves the balance between precision and recall, and frequently outperforms standalone aligners across domains.
- Ensemble composition directly affects the precision-recall trade-off: heterogeneous cross-paradigm ensembles typically improve precision, while homogeneous LLM ensembles more often achieve higher overall F1 scores.
- These results show that systematic ensemble learning provides a robust and reproducible strategy for OA, while offering practical guidance for selecting ensemble compositions under different alignment scenarios.
Individual aligners and ensemble configurations were evaluated on eight benchmark tasks from five OAEI tracks, spanning biomedical domains to relations beyond equivalence.