{"id":1461,"slug":"tesco-clubcard-1994-trial-9-stores-50m-tx","title":"Tesco Clubcard 1994 trial — 9-14 stores over 3 months, >50 million transactions; dunnhumby analysed ~10pct sample","kind":"reference","scope":"business","status":"current","audiences":["kevin","smb-owner","candid-team"],"topics":["behavioral-economics","information-asymmetry","customer-retention"],"reference_body":"**Claim.** Tesco trialled the Clubcard programme in 1994 over three months in 9-14 stores, generating more than 50 million transactions in the first three months. dunnhumby analysed roughly a 10pct sample and generalised the findings, demonstrating that the loyalty signal could reveal customer behaviour at scale.\n\n**Source.** Humby, Hunt & Phillips, *Scoring Points* (2004) via mugleston.co.uk dissertation summary; Computer Weekly \"Clubcard at 30\" (accessed 2026-06-21).\n\n**Confidence.** Industry-consensus. Restated across multiple independent secondary sources tracing back to the participant-authored primary book.\n\n**Caveats.** Underlying narrative is participant-authored (dunnhumby founders) — directionally reliable but with predictable framing bias. The \"50M transactions in 3 months\" figure is reported from internal Tesco/dunnhumby data, not externally audited.\n\n**Implication / use.** Sets the *data-volume* baseline for the strongest documented loyalty-card win. Crucial when comparing to SMB: the Clubcard edge was extracted from a sample roughly equal to a typical SMB's lifetime transaction count. The mechanism generalises; the magnitude does not.","rationale_body":null,"metadata":null,"links":{"outgoing":[{"slug":"research-brief-information-asymmetry-decision-edge-june-2026","title":"Research notes (capture-layer): the affirmative, inward decision-edge case for data intelligence — information asymmetry applied to pricing, demand, risk, retention, targeting (June 2026)","kind":"research-notes","scope":"business","link_type":"depends-on"}],"incoming":[{"slug":"rule-smb-magnitudes-from-named-cases-dont-scale-down","title":"Rule: the mechanism generalises, the magnitudes do not — SMBs cannot extract the same uplift Tesco / AA / Progressive did","kind":"rule","scope":"business","link_type":"depends-on"},{"slug":"tesco-clubcard-overtook-sainsburys-doubled-share","title":"Tesco Clubcard — overtook Sainsbury's in 1995 within a year of launch; helped double grocery market share within ~3 years","kind":"reference","scope":"business","link_type":"relates-to"},{"slug":"maclaurin-epigraph-three-months-thirty-years","title":"Lord MacLaurin epigraph — \"you know more about my customers after three months than I know after 30 years\" (Tesco Clubcard, 1994)","kind":"reference","scope":"business","link_type":"relates-to"},{"slug":"tesco-lifestyles-segmentation-mailings","title":"Tesco \"Lifestyles\" — behavioural segmentation system used to target Clubcard mailings (SS, weakest evidence in the targeting domain)","kind":"reference","scope":"business","link_type":"relates-to"},{"slug":"clubcard-data-quality-multiple-users-one-card","title":"Clubcard data-quality lesson — multiple users on one card produced false positives in mining (the \"garbage in\" warning from the best-documented winner)","kind":"reference","scope":"business","link_type":"relates-to"}]},"created_at":"2026-06-21T01:14:48.705Z","updated_at":"2026-06-21T01:14:48.705Z"}