Found & Trusted
Development
Writing
Book a call
Knowledge Base
/
topic: accuracy-risk-published-data
Topic:
accuracy-risk-published-data
12 entries tagged
accuracy-risk-published-data
.
Rules (3)
rule
R6 — Every published number gets a label (what it is) and a vintage (how fresh); the Zestimate defence depends on it
rule
R4 — Commit to a documented input-refresh schedule before shipping any customer-facing calculator; if you won't, don't ship it
rule
R3 — Label every published estimate as an estimate, and show its vintage prominently
Reference entries (9)
reference
Clubcard data-quality lesson — multiple users on one card produced false positives in mining (the "garbage in" warning from the best-documented winner)
reference
IBM/Ponemon Cost of a Data Breach (Jul 30, 2024; 604 orgs; Mar 2023-Feb 2024): Canadian average CA$6.32M (down from CA$6.94M in 2023); 2025 figure ~CA$6.98M per separate edition
reference
Zillow Zestimate published error rates — ~1.9% on-market, ~7.5% off-market; lawsuits; 7th Circuit 2019 sided with Zillow partly because "estimate" was clearly labelled
reference
ACS 5-Year Estimates carry margins of error that produce "false positives" in small/rural areas if ignored
reference
Moving industry: online cost calculators "often cannot reliably predict the true scope"; reputable movers require in-home/virtual surveys; FMCSA 110% rule applies
reference
Solar incentives can change daily — unmaintained solar calculators actively mislead
reference
Solar calculator inaccuracy: three Wolcott St (Newton MA) homes of 1,885 / 881 / 493 sq ft returned near-identical savings ($30k-$32k) on Google Project Sunroof
reference
Industry rule of thumb: estimates that exceed actual cost by more than ~10-20% require re-discussing scope
reference
A detailed online estimate with no reasonable basis can expose you to misrepresentation or negligence — even when labelled "estimate"
