Accuracy-radius attrition

data_quality

Geolocation vendors ship a per-record error bar (accuracy radius, and in some products per-field confidence factors), but downstream ad-serving and reporting schemas carry only the point or cell, so the uncertainty is discarded at the first hop and delivered geography arrives dressed as exact.

Detection

Delivery or reporting records carry a location with no accompanying radius/confidence field although the upstream source publishes one per record.

Mitigation

Propagate the source's accuracy radius and confidence through every hop that carries the location
Pin the statistical meaning of the radius (containment probability) in the schema — vendor documentation may not state one
Reject 'exact' locations whose source is a probabilistic lookup

Read the full article: IP Lookup To H3 →

Affected conversions

Point → H3 exact
IP lookup → H3 (probabilistic crosswalk) approximate