The fourth step in the conventional transportation forecasting model is the
TRAFFIC ASSIGNMENT
Types of Traffic Assignment
-ALL-OR-NOTHING ASSIGNMENT
-CONSTANT ASSIGNMENT RATIO
-USER EQUILIBRIUM TRAFFIC ASSIGNMENT
-SYSTEM OPTIMIZATION TRAFFIC ASSIGNMENT
In this method the trips from any origin zone to any destination zone are loaded onto a single, minimum cost, path between them.
ALL-OR-NOTHING TRAFFIC ASSIGNMENT
In this method, it is assumed that the number of trips assigned to a route is inversely proportional to the travel time or cost of that route.
CONSTANT ASSIGNMENT RATIO