{
  "kind": "fact",
  "studySlug": "llmstxt-effect",
  "slug": "the-significance-test-comes-back-null",
  "title": "The significance test comes back null",
  "description": "An analysis of the llms.txt effect on citation rates reveals no statistically significant impact.",
  "lastUpdated": "2026-03-14",
  "lastTested": "2026-03-14",
  "sourceStudyUrl": "/trakkr-research/llmstxt-effect",
  "sourceStudyTitle": "The llms.txt Effect",
  "claimIds": [
    "llmstxt-effect:p-value"
  ],
  "relatedSlugs": [
    "answer:which-industries-adopt-llms-txt-most",
    "answer:does-llms-txt-help-you-even-if-it-does-not-raise-citations",
    "tracker:llmstxt-adoption-by-sector-tracker"
  ],
  "methodologySummary": "Built from HTTP scans of 37,894 AI-cited domains, linked to 337,362 citations and 882 citation snapshots in the Trakkr corpus.",
  "limitations": [
    "This is an observational study. It measures correlation with citation outcomes, not a controlled experiment.",
    "Adoption is uneven by sector, so raw averages can hide category concentration in SaaS and developer tooling.",
    "A null citation effect does not mean llms.txt has zero operational value for every workflow. It means the study did not find a measurable citation lift."
  ],
  "keywords": [
    "llms.txt",
    "llms txt effect",
    "AI citations",
    "does llms.txt work"
  ],
  "schemaHints": {
    "pageType": "Article",
    "includeDataset": true
  },
  "claim": "The llms.txt citation comparison returns a Mann-Whitney p-value of 0.85, indicating no statistically significant citation effect.",
  "supportingMetrics": [
    {
      "label": "Mann-Whitney p-value",
      "value": "0.85",
      "detail": "No statistically significant citation effect detected."
    }
  ],
  "whyItMatters": "Strategists and operators should allocate resources away from llms.txt implementation and treat it as a low priority until empirical evidence demonstrates a measurable impact on citation frequency.",
  "citationBlock": {
    "quote": "The llms.txt citation comparison returns a Mann-Whitney p-value of 0.85.",
    "attribution": "The llms.txt Effect - Trakkr Research",
    "url": "https://trakkr.ai/trakkr-research/llmstxt-effect/facts/the-significance-test-comes-back-null"
  }
}