13.9 Geospatial visualization
Use a map when location is part of the question, not merely because geographic fields exist. A choropleth often needs a relevant denominator such as population, households, eligible customers, or facility capacity.
A reproducible mapping workflow should:
- choose the geography that matches the decision;
- join with stable identifiers rather than labels alone;
- inspect unmatched, duplicated, and missing regions;
- select an appropriate coordinate reference system;
- simplify geometry only after checking important shapes;
- use an inset when a dense area would otherwise be unreadable; and
- include data, boundary, and basemap attribution.
The UPGo tutorial demonstrates a script-based R workflow using sf, ggplot2, and census geography, including themes and inset maps (Wachsmuth 2019). CensusMapper and cancensus can support identification and retrieval of Canadian census variables and geometries (CensusMapper, n.d.; Bergmann, Shkolnik, and Jacobs 2026).
Worked Example: Comparing Visits and Utilization
An NVRW map of total visits makes the most populated service area appear dominant. A second map shows visits per 1,000 residents. One rural area now has the highest utilization rate despite having fewer total visits.
Neither map is universally better. Counts support total capacity decisions, while rates support comparison of relative service use. The report presents both and explains the different questions.