Congestion Flashcards
Lesson 4
How does congestion arise
bottleneck: when more people want to use a facility at a particular time than can comfortably use it
what is the come as you please system
let drivers decide for themselves when to use tunnel with no guidance
what are the two kinds of costs under a come as you please system
-waiting costs (proportional to the amount of time you wait, time spent in traffic, cost of gas wasted while waiting)
-schedule delay costs (cost when using facility at time not optimal for the rider: cost from using facility late and early)
what are schedule delay costs
the cost of being late for work or an appointment
what are schedule delay costs
-the costs of being late for work or an appointment
-the cost of being early (cost of giving up time)
What happens if you plan to go through the tunnel early or late?
You’ll avoid traffic, resulting in small waiting costs but big schedule delay costs
What are the consequences of planning to go through the tunnel very close to 8:30 am?
Schedule delay costs will be small, but waiting costs will be big
What can be concluded if all drivers are identical and strive to reduce their costs?
No time of arrival can be any better (or worse) than any other
Fill in the blank: If you go through the tunnel early or late, your waiting costs will be _______.
small
Fill in the blank: If you go through the tunnel close to 8:30 am, your waiting costs will be _______.
big
what is the equilibrium of the come as you please system
-every driver except the first and last is imposing an external cost on some other driver
-the closer you are to the optimal time you arrive, the more time you spend in line, the greater the burden imposed on other people
Describe a reservation system
-Schedule delay cost at earliest time would still be same as schedule delay cost at latest time
-schedule delay cost would be same, but no waiting cost
Benefits of a reservation system
-almost everyone is better off and no one is worse off
reservation system vs. come as you please
-some people are better off than others in a reservation system
-everyone is equally miserable when people decide on their own
What does the toll in a Congestion Pricing System achieve?
It makes every time equally attractive: the total cost is the same.
What are the components of the total cost in a Congestion Pricing System?
Schedule delay cost and toll cost.
What is the effect of the Congestion Pricing System on individuals’ arrival times?
No one wants to change his or her arrival time.
How is the Congestion Pricing System described in terms of reservations?
It functions as a ‘reservation system’ without actually requiring reservations.
What are waiting costs considered in the context of a Congestion Pricing System?
Pure waste.
What is the difference between waiting costs and tolls in a Congestion Pricing System?
Waiting costs are waste; tolls are a transfer.
Who benefits from tolls in a Congestion Pricing System?
The toll authority.
Fill in the blank: Nobody gains from ______ costs.
waiting
