Chapter 3 Diffusion through Space and Time

Spatial Diffusion The spread of some phenomenon (not only diseases, but also cultural traits and innovations) over space and through time from a limited number of origins.

Relocation Diffusion Relocation Diffusion – Occurs when the items being diffused leave the original areas behind as they move to new areas. Examples??? Brainstorm at least three examples with a partner. Language, religion, Chinese who settle in the United States and bring cultural food and tradition with them.

The Spread of Cricket Figure 3.1 (p. 63)

Expansion Diffusion Expansion Diffusion – the process whereby the item spreads geographically by passing from one person to another while remaining with the first person. Examples??? Turn to a new partner and brainstorm at least three examples. Henna – an Indian tradition coming to the United States or the spread of disease (Fashion)

Relocation Diffusion The key distinction between relocation and expansion diffusion is whether the number of adopters is expanding. Expansion Diffusion vs.

Figure 3.2 (p. 64) S-Curve Percentage of Population That Adopts the Idea or Innovation Majority Adopters Laggards Innovators Time

Figure 3.3 (p. 64) U.S. Cell Phone Subscribers

Figure 3.4 (p. 65) What other phenomena might follow the S-curve adoption pattern? Come up with at least three examples with a NEW partner!

Contagious Effects Figure 3.5a (p.66)

Figure 3.6 (p. 67) The Spread of Islam

Figure 3.5b (p. 66) Hierarchical Effects

Figure 3.5b (p. 66) Hierarchical Effects

Figure 3.5b (p. 66) Hierarchical Effects

Larger cities are generally the first to experience phenomena which spreads by hierarchical diffusion. Online Activity Major U.S. Cities

Biased innovation – diffuse according to social context instead of spatial context. Biased innovators are less accessible to people of a certain gender, class, ethnicity or age. Example: Civilian space travel is becoming MORE popular but a huge barrier exists – the cost.

Barriers to diffusion – A physical feature such as a lake or mountain or cultural impediment to the spread of an item.

A biased innovation a barrier to diffusion? or ownership of BMW vehicles a joke in Quebec which doesn't translate into English the spread of certain ring tones the popularity of a new movie the popularity of a new movie in Spanish a software program subject to export restrictions a disease found only among the mammals on a large island

Other Examples of Diffusion clothing fads video games radio broadcasting punk rock computers chemical fertilizers for farming anti-HIV drug cocktail

Name That Key Term

A process in which items being diffused leave the originating areas as they move to new areas (i.e. the items diffuse with people migrating). Relocation Diffusion Innovations (or diseases) that are less (or more) accessible to people of a certain gender, class, age, or ethnicity. This diffusion theory emphasizes social context in addition to spatial context. Biased Innovation Physical, political, cultural, or economic impediments to diffusion. The spread of some phenomenon over space and through time from a limited number of origins. Spatial Diffusion Barriers to Diffusion

A system of cities consisting of various levels, with few cities at the top level and increasingly more settlements on each lower level. The position of a city within the hierarchy is determined by the types of central place functions it provides. Urban Hierarchy A process in which the items being diffused remain and often intensify in the origin area as new areas are being affected (i.e. the items diffuse from person to person). Expansion Diffusion

Diffusion of a disease, cultural trait, idea, or innovation that spreads outward from a node or epicenter in wave-like fashion. This diffusion emphasizes the frictional force of distance in explaining the spread of things in time and space. Contagious Effects Diffusion of a disease, cultural trait, idea, or innovation from larger to smaller places, leaping over nearby but small places in the early stages. This diffusion emphasizes the size distribution of urban places (i.e. the urban hierarchy) in explaining the spread of things over time and space. Hierarchical Effects

Tracking the AIDS Epidemic in the United States: Diffusion through Space and Time Case Study Chapter 3

After completing this chapter, you will be able to: Define and give examples of hierarchical diffusion. Define and give examples of contagious diffusion. Interpret a scatter diagram. Interpret animated maps that change over time. Calculate cumulative totals and make a cumulative graph. Describe the diffusion of AIDS in the United States.

Background on AIDS What is AIDS? AIDS in Africa Global pathways and global hotspots Current situation in the United States

Figure 3.8 (p. 71) Population Pyramid for Botswana

Figure 3.10 (p. 72) Probable Early Diffusion of AIDS

Figure 3.11 (p. 73) World HIV/AIDS Rate for Adults

Activity 1: Mapping the Diffusion of AIDS Online Activity

Figure 3.13 (p. 80) Activity 2: Distance from Initial Centers Typical Downward-Sloping Scatterplot

Online Activity

Activity 3: S-Curves Online Activity