{
  "schema": "vedokrok.public-item.v1",
  "release_id": "MHC-RPUB-20260920-75ad787a",
  "url": "/knowledge/choose-the-average-that-fits-the-question",
  "id": "MHC-D-RESEARCH-0248",
  "version": "0.1.0",
  "title": "Choose the average that fits the question",
  "summary": "The arithmetic mean can be correct and still describe nobody's ordinary day.",
  "kind": "heuristic",
  "body": "Compare the mean with the median and inspect the distribution. The mean retains the influence of large magnitudes; the median identifies the ordered middle. Decide whether the question concerns totals and load, a typical case, or something else before selecting the summary.",
  "limits": [
    "A median does not make expensive or dangerous tail cases irrelevant."
  ],
  "topics": [
    "union-numerical-reasoning"
  ],
  "intents": [],
  "source_ids": [
    "RS-26830AF1759FF4A2"
  ],
  "evidence": [
    {
      "claim": "The mean uses every magnitude, while the median is based on the ordered middle; extreme values can therefore affect them differently.",
      "source_id": "RS-26830AF1759FF4A2",
      "role": "supports",
      "note": "Neither measure is automatically the best summary for every decision.",
      "locator": "Definition of Location; effects of heavy tails"
    }
  ],
  "use_when": [
    "A single 'average' seems unlike most observations."
  ],
  "avoid_when": [
    "A median does not make expensive or dangerous tail cases irrelevant."
  ],
  "example": "Durations of 1, 1, 1, 1 and 21 minutes have a mean of 5 and a median of 1. The long case still matters for total workload.",
  "check": "The chosen summary serves the decision rather than merely sounding more favorable.",
  "sources": [
    {
      "id": "RS-26830AF1759FF4A2",
      "title": "NIST/SEMATECH e-Handbook, 1.3.5.1: Measures of Location",
      "url": "https://www.itl.nist.gov/div898/handbook/eda/section3/eda351.htm"
    }
  ],
  "relations": [
    {
      "from": "MHC-D-RESEARCH-0248",
      "to": "MHC-D-RESEARCH-0250",
      "type": "useful_with",
      "url": "/knowledge/put-variation-beside-the-average"
    }
  ],
  "collections": [
    {
      "id": "RC-D976097B2A42D9AC",
      "title": "Make the numbers answer the right question",
      "url": "/collections/make-the-numbers-answer-the-right-question"
    }
  ]
}