[all infographics screencapped from WalkScore.com]
These examples show that measured amenity density is quite sensitive to the radius used, but this sensitivity is still insignificant compared to the large differences in prosperity (wealth density) between cities.
Redwing, Minnesota:
3 restaurants within 0.05 miles = 147 / sqkm
8 restaurants within 0.1 miles = 98.3 restaurants / sqkm (Downtown Redwing)
13 restaurants within 0.4 miles = 9.99 / sqkm (Redwing Area)
4 coffee within 0.1 miles = 49.2 coffee / sqkm (Downtown Redwing)
6 coffee within 0.7 miles = 1.50 / sqkm (Redwing Area)
5 groceries within 0.1 miles = 61.4 groceries / sqkm (Downtown Redwing)
8 groceries within 1.0 miles = 0.983 / sqkm (Redwing Area)
9 shopping within 0.1 miles = 111 shopping / sqkm (Downtown Redwing)
13 shopping within 1.0 miles = 1.60 / sqkm (Redwing Area)
Restaurants + Coffee + Groceries + Shopping:
319 / sqkm (Downtown Redwing)
14 / sqkm (Redwing Area)
Hennepin/Lake, Minneapolis:
4 restaurants in 0.03 mile radius = 1410 / sqmi = 546 / sqkm
7 restaurants in 0.06 miles = 239 / sqkm
13 restaurants in 0.08 miles = 250 / sqkm
27 restaurants in 0.1 miles = 332 restaurants / sqkm (Hen/Lake, Minneapolis)
Density falls as we expand the radius beyond the commercial node:
36 restaurants in 0.2 miles = 111 / sqkm
47 restaurants in 0.4 miles = 36.1 / sqkm (Uptown Minneapolis)
5 coffee in 0.1 miles = 61.4 coffee / sqkm (Hen/Lake, Minneapolis)
16 coffee in 0.4 miles = 12.3 / sqkm (Uptown Minneapolis)
7 groceries in 0.5 miles = 3.44 groceries / sqkm (Hen/Lake, Minneapolis)
12 shopping in 0.09 miles = 182 shopping / sqkm (Hen/Lake, Minneapolis)
Restaurants + Coffee + Groceries + Shopping: 579 / sqkm (Hen/Lake, Minneapolis)
Wider area: Restaurants + Coffee + Groceries: 52 / sqkm (Uptown Minneapolis)
Hanoi Old Town:
3 restaurants in 0.05 km radius = 382 / sqkm
7 restaurants in 0.07 km radius = 455 / sqkm
14 restaurants in .09 km radius (0.0254 sqkm area) = 550 restaurants / sqkm (Hanoi)
3 coffee in 0.08 km radius = 149 / sqkm
15 coffee in 0.1 km radius (0.0314 sqkm area) = 446 coffee / sqkm (Hanoi)
4 groceries in 0.5 km radius = 5.09 / sqkm [underestimate]
13 groceries in 0.6 km radius (1.13 sqkm area) = 11.5 groceries / sqkm (Hanoi)
3 shopping in 0.06 km radius = 265 / sqkm
5 shopping in 0.08 km radius = 249 / sqkm
8 shopping in 0.09 km radius = 314 / sqkm
12 shopping in 0.1 km radius (0.0314 sqkm area) = 382 shopping / sqkm (Hanoi)
Restaurants + Coffee + Groceries + Shopping: 1389 / sqkm (Hanoi Old Town)
Chicago Loop:
10 restaurants in 0.08 mile radius (0.0521 sqkm area) = 192 restaurants / sqkm (Chicago Loop)
12 coffee in 0.1 mile radius (0.0814 sqkm area) = 147 coffee / sqkm (Chicago Loop)
11 groceries in 0.5 mile radius (2.03 sqkm area) = 5.41 groceries / sqkm (Chicago Loop)
12 shopping in 0.08 miles = 230 / sqkm
39 shopping in 0.1 miles = 479 shopping / sqkm (Chicago Loop)
74 shopping 0.2 miles = 227 / sqkm
Restaurants + Coffee + Groceries + Shopping: 823 / sqkm (Chicago Loop)
Chicago Chinatown:
14 restaurants in 0.07 mile radius (0.0399 sqkm area) = 351 restaurants / sqkm (Chicago Chinatown)
7 coffee in 0.2 mile radius (0.325 sqkm) = 21.5 coffee / sqkm (Chicago Chinatown)
10 groceries in 0.1 mile radius (0.0814 sqkm area) = 123 groceries / sqkm (Chicago Chinatown)
9 shopping in 0.1 mile radius (0.0814 sqkm area) = 111 shopping / sqkm (Chicago Chinatown)
Restaurants + Coffee + Groceries + Shopping: 606 / sqkm (Chicago Chinatown)
Ginza, Tokyo:
4 restaurants in 0.05 km radius (0.00785 sqkm) = 509 / sqkm
[correcting to 0.04 km => 796 / sqkm]
9 restaurants in 0.07 km radius (0.0154 sqkm) = 585 / sqkm
[correcting to 0.06 km => 796 / sqkm]
19 restaurants in 0.08 km radius (0.0201 sqkm) = 945 / sqkm
[correcting to 0.07 km => 1234 / sqkm]
29 restaurants in 0.09 km radius = 1140 / sqkm
[correcting to 0.08 km => 1442 / sqkm]
62 restaurants in 0.1 km radius = 1974 / sqkm
157 restaurants in 0.2 km radius = 1249 restaurants / sqkm (Ginza, Tokyo)
10 coffee in 0.09 km radius = 393 / sqkm
29 coffee in 0.1 km radius = 923 / sqkm
62 coffee in 0.2 km radius = 493 / sqkm
[NB: the repetition of 29 & 62 is probably a WalkScore artifact]
128 coffee in 0.3 km radius = 453 cofee / sqkm (Ginza, Tokyo)
4 groceries in 0.09 km = 157 / sqkm
7 groceries in 0.1 km = 223 / sqkm
15 groceries in 0.2 km = 119 / sqkm
45 groceries in 0.3 km = 159 groceries / sqkm (Ginza, Tokyo)
3 shopping in 0.05 km = 382 / sqkm
9 shopping in 0.08 km = 448 / sqkm
30 shopping in 0.1 km = 955 / sqkm
106 shopping in 0.2 km = 844 shopping / sqkm (Ginza, Tokyo)
Restaurants + Coffee + Groceries + Shopping: 2705 / sqkm (Ginza, Tokyo)
Central Ginza:
11 restaurants in 0.07 km = 715 / sqkm
19 restaurants in 0.09 km = 747 / sqkm
53 restaurants in 0.1 km = 1687 / sqkm
178 restaurants in 0.2 km = 1416 restaurants / sqkm (Central Ginza)
8 coffee in 0.06 km = 707 / sqkm
33 coffee in 0.1 km = 1050 / sqkm
65 coffee in 0.2 km = 517 coffee / sqkm (Central Ginza)
6 groceries in 0.06 km = 531 / sqkm
25 groceries in 0.1 km = 796 / sqkm
46 groceries in 0.2 km = 366 groceries / sqkm (Central Ginza)
11 shopping in 0.04 km = 2188 / sqkm
36 shopping in 0.09 km = 1415 / sqkm
63 shopping in 0.1 km = 2006 / sqkm
125 shopping in 0.2 km = 995 shopping / sqkm (Central Ginza)
Restaurants + Coffee + Groceries + Shopping: 3294 / sqkm (Central Ginza, Tokyo)
Summary
(Restaurants + Coffee + Groceries + Shopping)
Central Ginza: 3294 / sqkm
Ginza: 2705 / sqkm
Hanoi: 1389 / sqkm
Chicago Loop: 823 / sqkm
Chicago Chinatown: 606 / sqkm
Hen/Lake, Minneapolis: 579 / sqkm
Downtown Redwing: 319 / sqkm
Redwing Area: 14 / sqkm
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