[Talk-us] Correct source for population=* tags on US metropolitan cities

[Minh Nguyen]

Vào lúc 19:25 2021-01-30, Clifford Snow đã viết:
> I was subtly trying to point out the futility of using data from these areas. 
> The government can change them at will. And apparently it looks like 
> they are going to adjust them again. I don't mind updating a city's 
> boundary but this game they play with statistical areas is nuts. Sure we 
> could add in all the census areas so someone could add up the number but 
> how does that help OSM.

To be clear, Joseph had originally proposed changing the standard for 
population tags on place=* nodes, not boundaries, emphasizing that the 
two represent related but not strictly identical concepts.

Moreover, the proposal was to adopt urbanized areas [1] as the new 
standard, not metropolitan statistical areas. Urbanized areas are 
somewhat better suited for population-based label sizes because they're 
much more granular. They're delineated by census tracts and blocks 
rather than county boundaries (which can be vast in one state and 
minuscule in another), so there are a lot more urbanized areas.

In the document you shared, the OMB is proposing to change the threshold 
between micropolitan and metropolitan statistical areas. There's a much 
lower threshold between urbanized areas and urban clusters. Both 
thresholds are uniform across the whole country, so in populous states 
like California, they don't match popular notions of the cutoff for a 
city versus a small town.

 From a cartography standpoint, Joseph is right that the population of a 
city proper is not always the most useful basis for sizing the city's 
label. But I'm concerned that making place label sizing purely 
data-driven would require incorporating some editorial decisions into 
the data, because places aren't purely demographic constructs. The 
alternative would be for renderers to apply heuristics or exceptions in 
postprocessing.

[1] 
https://www.census.gov/programs-surveys/geography/about/faq/2010-urban-area-faq.html

-- 
minh at nguyen.cincinnati.oh.us