10.3. All-or-nothing assignment

Try these first

1. 1.

   What does the All-or-Nothing method assign trips based on?

   Hint

   Think about how simple this model is.

2. 2.

   Is travel time in AON assignment variable based on congestion?

   Hint

   Consider how traffic might change during rush hour.

3. 3.

   What does the All-or-Nothing assignment method assume?

   • All trips are allocated to multiple paths.
   • All trips are assigned to one path.
   • Travel time varies with congestion.

   Hint

   Think about the name of the method.

4. 4.

   True or False: The All-or-Nothing model considers multiple paths for each trip.

   • True
   • False

   Hint

   Focus on the definition of AON.

5. 5.

   A city has two main routes from point A to point B. Route 1 is 20 minutes if it's unblocked and Route 2 is 15 minutes. However, Route 1 can sometimes become congested. Explain how using AON might lead to miscalculations in travel times.

   Hint

   Consider what happens if traffic builds up on the routes.

6. 6.

   Assuming a network has multiple origins and destinations with varying cost paths, suggest an alternative assignment method that could be applied after AON, explaining its advantages.

   Hint

   Think about how you can balance flow across paths.