Application of an Elementary Spatial Interaction Equation Copyright © 1998-2020, Dr. Jean-Paul Rodrigue, Dept. of Global Studies & Geography, Hofstra University. For personal or classroom use ONLY. This material (including graphics) is not public domain and cannot be published, in whole or in part, in ANY form (printed or electronic) and on any media without consent. This includes conference presentations. Permission MUST be requested prior to use. W X Y Z Ti W 100,000 100,000 X 100,000 50,000 25,000 175,000 Y 50,000 50,000 Z 25,000 25,000 Tj 100,000 175,000 50,000 25,000 350,000 X 2,000,000 Y Z W 800 km 800 km 400 km 2,000,000 1,000,000 k = 0.00001 (people per week) 2,000,000 Weight (P) Distance (D) Constant (k) Centroid (i) Interaction (T) Elementary Formulation