{
  "slug": "ctr-bucket-support",
  "name": "Position-bucket support",
  "aliases": [
    "Bucket instances",
    "Low-confidence bucket flag"
  ],
  "definition": "How many keyword-and-page instances a position bucket's click rate was fitted from, and the flag raised when that count falls below the reliability floor.",
  "category": "Content opportunity",
  "type": "raw measure",
  "unit": "keyword-and-page instances per position bucket",
  "direction": "higher-better",
  "verification": "verified",
  "calculation": "instances = COUNT(*) of the keyword-and-page rows grouped into that branded × intent × device × position bucket. A bucket fitted from fewer instances than the reliability floor (default 5) is flagged low-confidence; flagged buckets are kept in the fit rather than dropped.",
  "aggregation": "A count per bucket. A cell in which no bucket clears the floor is reported as a sparse cell, its entire curve is weak, not just one point of it.",
  "grain": "One position bucket inside one branded × intent × device cell.",
  "dimensions": [
    "position bucket",
    "brand",
    "intent",
    "device"
  ],
  "requiredFilters": [
    "date range"
  ],
  "sources": [
    "search-console"
  ],
  "reports": [
    "ctr-opportunity-report",
    "search-opportunity-report"
  ],
  "skills": [
    "ctr-opportunity-audit",
    "striking-distance-sprint"
  ],
  "verbs": [
    "ctr_curve_model",
    "striking_distance"
  ],
  "rungs": [
    "R2"
  ],
  "levers": [
    "L3"
  ],
  "questions": [
    "How reliable is our CTR curve at these positions?",
    "Which segments do not have enough data to model?"
  ],
  "interpretation": "The reason a curve is trustworthy or is not. Where support is thin, the expected CTR, the gap and every upside figure derived from it are thin too, and the affected rows are labelled rather than dropped, so a worklist never quietly loses its weakest half.",
  "caveats": [
    "The floor is a caller-settable convention, not a power calculation, it does not correspond to a confidence level.",
    "Support counts instances, not impressions, so a bucket can clear the floor on many tiny rows.",
    "Widening the fitted window raises support but ages the curve, and the curve drifts."
  ],
  "freshness": "1 to 2 days behind, Google's own reporting lag. Any answer touching the last 48 hours says so on the card.",
  "failureModes": [
    "Dropping low-confidence rows from a worklist instead of labelling them.",
    "Reading a high instance count as high impression volume."
  ],
  "notSameAs": [],
  "related": [
    "weighted-ctr",
    "expected-ctr",
    "fallback-ctr-prior"
  ],
  "workflows": [],
  "lastVerified": "2026-08-04"
}