Hagerstrand model

• Hagerstrand developed a model to show contagious diffusion of disease

  
• outline the neighbourhood effect

  • the probability of contact between a carrier and non-carrier is determined by distance
  • people living closer to carriers have a higher probability of contracting the disease than a person further away
• describe the shape of the curve

  • the start is slow
  • then the number of infected people rapidly increases
  • then levels out when most of the susceptible population have been infected
  • diffusion of disease may be interrupted by physical barriers