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The largest city in each 10x10 degree latitude/longitude box

blog.plover.com

31–40 of 164 posts

Re: The largest city in each 10x10 degree latitude/longitude box

#31
post #25

I quibble with the description of the shapes bounded by 10 degrees of longitude and latitude as "rectangles" - they're not even planar shapes, and their adjacent sides certainly aren't at right angles. Some of them don't even have four sides. This bears considering when looking at the map, because some of those regions are much, much smaller than others.

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Re: The largest city in each 10x10 degree latitude/longitude box

#32
post #25

I quibble with the description of the shapes bounded by 10 degrees of longitude and latitude as "rectangles" - they're not even planar shapes, and their adjacent sides certainly aren't at right angles. Some of them don't even have four sides. This bears considering when looking at the map, because some of those regions are much, much smaller than others.

He's not making a mathematical definition of the areas. 'area' or 'box' is a simple description that everyone can understand. And the map projection used does form squares.

Re: The largest city in each 10x10 degree latitude/longitude box

#33

TIL Atlanta, GA has fewer people than Jacksonville, FL. The Atlanta metropolitan area has a lot more people.

This is the problem with how we define cities. Jacksonville is technically the largest city in all of Florida too, but that is because it annexed almost all of its suburbs, so the whole "metro" area is just on city, which is quite different then most other American cities.

Re: The largest city in each 10x10 degree latitude/longitude box

#34

I love how this says something about the biases that exist in making legible maps. Toronto isn’t even shown. Any time to read a map, remember that at different scales, there’s an editorial opinion, whether direct or algorithmic, on what you see.

It’s not particularly biased to say that New York is larger than Toronto, in my opinion.

Re: The largest city in each 10x10 degree latitude/longitude box

#35

I love how this says something about the biases that exist in making legible maps. Toronto isn’t even shown. Any time to read a map, remember that at different scales, there’s an editorial opinion, whether direct or algorithmic, on what you see.

Isn't that the point of the map (show the most populous city in each box?) Or you didn't get what the map is trying to do?

Re: The largest city in each 10x10 degree latitude/longitude box

#36
post #7

Why are some empty ocean squares colored dark blue and some light blue? Does light blue mean there is some land mass there but it's uninhabited?

Yes. That’s the concept I believe. I’m not sure how big a landmass had to be to make the map though.

It would be good if empty pieces of land were shaded differently, too.

Re: The largest city in each 10x10 degree latitude/longitude box

#37
post #25

I quibble with the description of the shapes bounded by 10 degrees of longitude and latitude as "rectangles" - they're not even planar shapes, and their adjacent sides certainly aren't at right angles. Some of them don't even have four sides. This bears considering when looking at the map, because some of those regions are much, much smaller than others.

[deleted]

Re: The largest city in each 10x10 degree latitude/longitude box

#39
post #19

I think something more interesting might be like a voronoi diagram of all cities such that the city is in like the top 5 within a 1000 miles radius or something (or just that but without the voronoi part). This should preserve the fact that only the largest cities in some area are present, but eliminate the arbitrariness of the boundaries. I think you would want to compute this with a sweep line algorithm.

A map projection that preserves area would be better, otherwise there's an excessive number of cities in the far northern hemisphere, and a lack of detail in the tropics.

Meanwhile, neither Sweden’s nor Norway’s capital is in the map. But two smaller Norwegian cities are.

I think this just teaches you the issue with discretization.

Re: The largest city in each 10x10 degree latitude/longitude box

#40

I’m fairly sure Toronto is larger than Chicago... EDIT: Yeah, back in 2013: https://www.thestar.com/news/city_hall/2013/03/05/torontos_p... - and I’m pretty sure it’s almost at or crossed the 3M mark (COVID may have tossed a wrench in the latter). Ah. It’s because Toronto is in the same box as _New York_ - my bad!

Chicago is having significant population loss, so that gap will only grow. I believe Houston is about to pass Chicago.
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