atlas — county-level North America, and thirteen superstates

Geography

Level

Measure

Classification

Natural breaks minimise variance inside each class. Quantile puts an equal number of counties in each, which always looks like a story. The map says which one it used.

The thirteen superstates

Regions are grown from the county map by contiguity-constrained clustering. Pick the axes; the borders follow.

Regions: 13 Weight on migration ties: 0.5 Minimum region size: 0.70 of an equal share

WHAT ELSE TO HONOUR

Keep states whole: 0.40

Redrawing a state is an energy barrier: a cut that falls inside one has to be worth more than leaving it alone. At 0 the map splits 38 of 53 states; at 0.40 it splits 13. Past about 0.40 the request collides with the population floor, and the floor wins — the status line says when it was dialled back.

Equal populations: 0.85 Floor under each region's water: 0.00 of a fair share

Water competes with equal populations, steeply: at 0.15 the worst-to-best water ratio falls from 21:1 to 15:1 and the population ratio rises from 1.5:1 to 3.1:1. It is USGS withdrawal, not rainfall — a county fed by a canal reads wet. Sea access is reported, not steered; nothing that was tried could move it. Why.

reading the boundary files…