Why absolute counts mislead
An uncorrected map of where an audience lives shows the largest cities, every time, for every audience. That is a map of population, not of affinity, and every competitor’s map looks the same.
Corrected for population, the picture changes: mid-sized regions with real concentration appear, and large cities often fall back to around the baseline, because their share of the audience simply reflects their size.
The formula
What the corrected map is used for
- Regional media allocation: spending in line with affinity rather than population.
- Out-of-home and retail siting: where physical presence meets an audience that is actually concentrated.
- Sponsorship geography: whether a property’s audience matches the sponsor’s distribution footprint, a mismatch national reach figures hide.
- Expansion sequencing: which regions to enter first.
Common mistakes
- Small regions, extreme values. A sparsely populated region can show a very high index on few people. Read the index with the absolute count.
- Borders are not audience borders. A catchment that crosses a state line shows up as two moderate values instead of one strong one.
- Affinity is not reachability. High regional affinity says the people are there, not that efficient media inventory exists.
How Rascasse uses it
Rascasse computes regional affinity per country against that country’s own population, for regions and cities and down to postal code where available. Because the baseline is national, values are comparable between brands within one market, not across markets.
Related use cases: Local Targeting & OOH, Media Planning, Sponsorship Activation.