{"slug": "evals-explained-in-plain-language", "title": "Evals, Explained in Plain Language", "summary": "Evals are standardized tests used to measure AI system performance, requiring unseen questions, scored answers, multiple test types, and comparisons across model versions to track trends over time. The piece explains that a single score can hide regressions, such as a model improving in reasoning while slipping in coding, and emphasizes monitoring scores across releases on relevant tests.", "body_md": "# Evals, Explained in Plain Language\n\nYou can't just *feel* that an AI system got better. You need a test — and a way to grade it.\n\n## Give it a test it's never seen\n\nIf it's already seen the answers, acing the test proves nothing. A real eval is questions it has **never met before**.\n\n## Score every answer\n\nEvery answer gets checked against the right one. No vibes — just a **tally** at the end.\n\n## One test isn't enough\n\nGood at math doesn't mean good at everything. Run **lots of different tests** — one score alone can hide a lot.\n\n## Compare the old model to the new one\n\n\"Better\" isn't automatic. The new model can climb in reasoning and safety and still **slip backwards** in coding, all at once.\n\n## Watch the score over time\n\nOne release can dip — that's normal. What matters is the **trend** across many releases, on the tests that actually matter to you. **Evals** — that's the real name for it.", "url": "https://wpnews.pro/news/evals-explained-in-plain-language", "canonical_source": "https://julin.ai/2026/08/23/evals-eli5/", "published_at": "2026-08-22 12:00:00+00:00", "updated_at": "2026-08-26 23:19:38.146787+00:00", "lang": "en", "topics": ["artificial-intelligence", "ai-research", "ai-tools"], "entities": [], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/evals-explained-in-plain-language", "markdown": "https://wpnews.pro/news/evals-explained-in-plain-language.md", "text": "https://wpnews.pro/news/evals-explained-in-plain-language.txt", "jsonld": "https://wpnews.pro/news/evals-explained-in-plain-language.jsonld"}}