Gravity Model
DESCRIPTION
Interactive gravity model of spatial interaction. Place cities with different populations and observe interaction strength (line thickness) based on I = k·P₁·P₂/d^n. Adjust distance exponent and constant k. Three presets: US Cities, World Cities, and Custom. Click any two cities to see the full calculation breakdown.
- gravity model
- spatial interaction
- population
- distance decay
- migration
- AP Human Geography
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