Push and pull factors in migration according to Everett S. Lee (1917-2007) are categories that demographers use to analyze human migration from former areas to new host locations.
Lee's model divides factors causing migrations into two groups of factors: push and pull.
Push factors are things that are unfavourable about the home area that one lives in, and pull factors are things that attract one to another host area.
[1][2] Sociology professor Hein de Haas has criticized the push-pull model for its inability to explain real world migration patterns.
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