Two Types of Diffusion Relocation Gets weaker in the core. Items being diffused leave the area of origin and move to new areas

Two Types of Diffusion Expansion Stays strong in the core When items spread geographically by passing from one person to another while remaining with the first person

Expansion Diffusion Spread of an innovation/idea…in such a way that the # of those influenced grows continuously larger, resulting in an expanding area of adoption This occurs when an IDEA or TRAIT spreads from one place to another

Expansion Diffusion Contagious Diffusion—spread of an idea /trait/concept through a group of people or an area equally without regard to social class, economic position, or position of power (no specific reason for why it goes where) Flu Gossip

Expansion Diffusion Hierarchical Diffusion—Spread of an idea through an established structure usually from people or areas of power down to other people or areas Urban areas to other urban areas and then to surrounding areas Music Fashion Wealthy people to middle class to lower class Technological innovations

Expansion Diffusion Stimulus Diffusion—the spread of an underlying principle even though the new groups “remix” your idea Follows an irregular patter Ideas are not readily or directly adopted because they are too vague, different, or impractical for immediate adoption

Relocation v. Expansion A is relocation diffusion as the person goes B is the expansion diffusion as the idea/trait moves or transports

Barriers to Diffusion Cultural Barriers Physical Barriers Some practices, innovations, ideas are not acceptable/adoptable in a particular culture (pork, alcohol, contraceptives) Physical Barriers Physical barriers on the surface may prohibit/inhibit adoption Not as relevant today b/c of technology Time-Distance Decay Farther from the source and the more time it takes, the less likely the innovation will be adopted (or it will develop differently) Technology makes this less prevalent

Density Frequency with which something occurs in space Arithmetic Density (total # of objects, people, phenomena, in a given area Population Density (Unit 2)—total number of people divided by total land area

Concentration The extent of a feature’s spread over space Clustered (close together) Dispersed (far apart) Density and Concentration of Baseball Teams

Pattern How things are arranged, geometrically speaking Linear distribution Grid patterns