Reproducing Claimed Hallucination Drops: From Gemini 2.0 Flash to Gemini 3.1 Pro

https://sophiasbestinsights.theglensecret.com/claude-opus-4-6-14-index-vs-claude-4-5-negative-how-much-better-a-data-first-comparison-feb-2026

This is a hands-on, data-first tutorial for engineers and researchers who want to test bold claims like "Gemini 2.0 Flash achieved 0.7% hallucination on basic summarization" or "Gemini 3.1 Pro cut hallucinations by 38 points