Retrieval-Augmented Generation (RAG) augments large language models (LLMs) with external knowledge, yet most RAG systems rely solely on vector-based semantic search, limiting their handling of structured or relational information. We propose a hybrid multi-source RAG architecture that unifies graph-based and vector-based retrieval within a single conversational framework. A prompt-driven orchestrator dynamically selects and fuses the appropriate source at runtime, leveraging graph databases for symbolic reasoning and vector stores for semantic similarity. Experimental evaluation with LLM-as-a-Judge scoring shows that the hybrid configuration consistently outperforms single-source baselines, achieving higher relevance, fluency, faithfulness, and interpretability without any additional training overhead.

Di Nicola, G., Iannucci, S., Torlone, R. (2026). Hybrid Multi-Source RAG for Context-Aware Conversational Data Access. In CEUR Workshop Proceedings. CEUR-WS.

Hybrid Multi-Source RAG for Context-Aware Conversational Data Access

Di Nicola G.;Iannucci S.;Torlone R.
2026-01-01

Abstract

Retrieval-Augmented Generation (RAG) augments large language models (LLMs) with external knowledge, yet most RAG systems rely solely on vector-based semantic search, limiting their handling of structured or relational information. We propose a hybrid multi-source RAG architecture that unifies graph-based and vector-based retrieval within a single conversational framework. A prompt-driven orchestrator dynamically selects and fuses the appropriate source at runtime, leveraging graph databases for symbolic reasoning and vector stores for semantic similarity. Experimental evaluation with LLM-as-a-Judge scoring shows that the hybrid configuration consistently outperforms single-source baselines, achieving higher relevance, fluency, faithfulness, and interpretability without any additional training overhead.
2026
Di Nicola, G., Iannucci, S., Torlone, R. (2026). Hybrid Multi-Source RAG for Context-Aware Conversational Data Access. In CEUR Workshop Proceedings. CEUR-WS.
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11590/548636
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