Wu Shixiong's Large Model Academy

Jul 23, 2026 · Artificial Intelligence

How to Prevent RAG from Hallucinating When No Answer Exists – Beyond Simple Similarity Thresholds

The article explains why a plain similarity‑threshold check cannot reliably stop Retrieval‑Augmented Generation from fabricating answers, introduces a four‑stage evidence‑control framework, details how to calibrate thresholds with balanced positive and negative samples, and outlines concrete actions for handling insufficient evidence.