Lookback window sensitivity

advertising

Audience size and composition for a 'visited store X' segment change substantially with the chosen lookback window (7 vs. 30 vs. 90 days); an undocumented or inconsistent window makes cross-campaign comparisons invalid.

Detection

Segment definitions across campaigns/vendors reference 'recent visitors' without a stated day count, or day counts differ between compared segments.

Mitigation

Standardize and document the lookback window per use case (planning vs. measurement)
Never compare audience sizes across segments built with different lookback windows

Affected conversions

Point → H3 exact
Point+radius → H3 approximate