Issues to consider: Data
Are you combining data sources?
- Scale
- Add the roads from a 1:250,000 UK road atlas to buildings from a 1:1,250 urban map, and the results will be very poor
- Data granularity
- If you’ve gathered data on postal area (YO, G, etc.), there’s no point plotting it on a map of postal districts (YO4, G67, etc.)
- Spurious accuracy
- “x lies within 100m of y”
- But x and y are drawn from data sources that are only precise to within 50m
- So x and y might be adjacent, or they might be 200m apart.