Accessibility

Accessibility (or just access) in transportation planning refers to the ease of reaching goods, services, activities and destinations, which together are called opportunities . For example, is there sufficient road capacity and are there sufficient parking spaces? Are there good options for public transport? What is the average travel time to reach the centre? Accessibility can be defined in terms of potential (opportunities that could be reached) or in terms of activity (opportunities that are reached).

A measure that is often used is to measure accessibility in a traffic analysis zone i is:

$Accessibility_{i}=\sum _{j}{Opportunities_{j}}\times f\left({C_{ij}}\right)$ where:

• $i$ = index of origin zones
• $j$ = index of destination zones
• $f\left({C_{ij}}\right)$ = function of generalized travel cost (so that nearer or less expensive places are weighted more than farther or more expensive places).

A city with a good accessibility has good possibilities to get emergency services to an incident location, or to get people quickly out of the area in case of any danger.

UNDER CONSTRUCTION