AP Human Geography

1. AP Human Geography GRAVITY MODEL

2. Uses size of location and distance as factors for travel Size of location takes precedent over distance The gravity model can be used to estimate: Traffic Flows Migration between two areas The number of people likely to use one central place Gravity Model

3. The GRAVITY MODEL of MIGRATION is a model, derived from Newton's law of gravity. • Newton's law states that: "Any two bodies attract one another with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between them."  • The GRAVITY MODEL of MIGRATION is used to predict the degree of interaction between two places

4. When used geographically, the words 'bodies' and 'masses' are replaced by 'locations' and 'importance' respectively,. • Importance can be measured in terms of population numbers, gross domestic product, or other appropriate variable.

5. The gravity model of migration is therefore based upon the idea that as the importance of one or both of the location increases, there will also be an increase in movement between them.

6. The farther apart the two locations are, however, the movement between them will be less. • This phenomenon is known as distance decay.

7. The simplistic version of the gravity model of migration is as follows: Mij = gravity model prediction of migration between origin i and destination j Pi = population of origin State i Pj = population of destination State j dij = distance from origin i to destination j

10. Earnest Ravenstein (1885) • 1) Most migrants only travel short distances to higher populated areas • 2) Migrants created gaps through the flow towards the higher populated areas filling up space between origin and destination • 3) Counter-current of migration at destination • 4) Long distance migrants flock towards world cities or large industrial areas • 5) The natives of towns are less migratory than those of the rural parts of the country • 6) Females are more migratory than males • Until recently • Men, or couples w/o children, young adult or senior citizens, no dependents

11. Migration Issues • Push factors • Things that push people to move away from a location • Pull factors • Things that draw people to a location • Forced Migration • People forced to leave a given place permanently • Usually based on ethnicity, religion, ideology, etc. • Refugees • People leaving a location for fear of persecution or death • War-torn nations, religious persecution • Cuban refugees • Intervening obstacles • Things that block migration streams • Intervening opportunities • Things that attract people while in the migration stream

12. Cultural Hearths • The center or starting point of a cultural trait • Regions can be defined by hearths • Examples? • Vatican City • Birth of Blues (Memphis, Tennessee)

13. Cultural Diffusion Relocation diffusion Hierarchical diffusion Contagious diffusion Stimulus diffusion Expansion diffusion

14. Acculturation Assimilation • A culture is completely dominated by another culture • Forced migration • Imperialization The spread of a cultural complex or a cultural trait from one location to another The process of another culture embracing or adding that cultural trait to their cultural complex