Theory of intervening opportunities attempts to describe the likelihood of migration. Its hypothesis is that this likelihood is influenced most by the opportunities to settle at the destination, less by distance or population pressure at the starting point.
Stouffer's law of intervening opportunities states, "The number of persons going a given distance is directly proportional to the number of opportunities at that distance and inversely proportional to the number of intervening opportunities." [1]
Stouffer theorises that the amount of migration over a given distance is directly proportional to the number of opportunities at the place of destination, and inversely proportional to the number of opportunities between the place of departure and the place of destination. These intervening opportunities may persuade a migrant to settle in a place in the route rather than proceeding to the originally planned destination. Stouffer argued that the volume of migration had less to do with distance and population totals than with the opportunities in each location. [2] This is in contrast to Zipf's Inverse distance law. [3]
There are links with Ravenstein's laws of migration 2, 3 and 4.
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The laws describing the behaviour of gases under fixed pressure, volume and absolute temperature conditions are called Gas Laws. The basic gas laws were discovered by the end of the 18th century when scientists found out that relationships between pressure, volume and temperature of a sample of gas could be obtained which would hold to approximation for all gases. These macroscopic gas laws were found to be consistent with atomic and kinetic theory, though with much scepticism over the reality of such a worldview.
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