Intervening Opportunities Model

The intervening opportunities model, introduced by Samuel Stouffer in 1940, explains the volume of migration between two places not by the physical distance separating them but by the number of opportunities available at the destination relative to the opportunities a migrant would encounter along the way. Its central claim is provocative: there is no necessary relationship between mobility and distance. Distance only matters because crossing more of it usually means passing more chances to stop. Formally, the number of people moving a given distance is directly proportional to the number of opportunities at that distance and inversely proportional to the number of intervening opportunities. Stouffer revised the model in 1960 to add 'competing migrants' — rivals converging on the same destination from other origins — giving spatial-interaction analysis an alternative to the gravity model that is grounded in opportunity structure rather than mass and distance.