Spatial Demography -- Migration

I.  Definitions and Significance

  1. Definition: permanent relocation of residential place and activity space
  2. Importance of studying migration patterns:
    1. Increasing global mobility in today's world, easier to migrate
    2. Integrative issue in geography, i.e. urbanization
    3. Policy relevance: labor markets--can labor and information flow freely between countries?  How can nations help refugee camps
  3. Migration Typology:
    1. Forced migration: individuals forced to leave their country, i.e. Africans brought to U.S. as slave labor
    2. Reluctant or fleeing migration: individuals are not forced out of their country, but leave because of warfare, political problems, or ethnic purging 
    3. Voluntary or volitional migration: individuals choose to relocate to new places because of opportunities offered in the new place
  4. Factors influencing the migration decision:
    1. Economic: utility maximization
    2. Push and pull factors: good weather, good services, family, etc.
    3. Spatial search, uncertainty, and hierarchical decision-making

II.  Migration models, equations and laws:

  1.     Demographic Accounting Equation:
              P(t + 1) = P(t) + I(t, t + 1) - E(t, t + 1)     net international migration
                              I = Immigration
                              E = Emigration
  2. Migration Biographies 
  3. Age Profile of Migration and the life course 
  4. Gravity Models
    1. Newton's law of universal gravitation
    2. Spatial Interaction
  5. Chain Migration 
             --people begin to migrate along certain channels
  6. Ravenstein's Migration Laws (1870's-1880's):
    1. Most migrants go only a short distance (gravity law)
    2. Longer-distance migration favors big-city destinations
    3. Most migration proceeds step by step
    4. Most migration is rural to urban
    5. Each migration flow produces a counter flow (i.e. return to place of birth)
    6. Most migrants are adults--families are less likey to make international moves
    7. Most international migrants are young males