AI Evaluation and Eval Sets 2026
Why Without eval: can't measure quality, prove improvement, catch regression. Build Eval Set 1. Collect 50-200 examples 2. Each: input + expected output 3. Cover edge cases 4. Real-user examples preferred Metrics Classification - Accuracy - Precision/Recall - F1 Generation - BLEU overlaps - ROUGE summary - BERTScore semantic LLM-as-Judge - Use stronger model to grade - Cost-effective for subjecti…