Fixed Route Transit Scheduling

1. Fixed Route Transit Scheduling Alexis Matrka Lauren Park Lan Wu

2. Two Different Approaches • 1. Level of Service Policy Orientation • Provide basic service level • I.e. train every 10 minutes for off-peak, and 5 minutes for peak • Generally used to provide minimum service

3. Two Different Approaches • 2) Demand Orientation • Look at current demand and provide enough seats that meet that demand • Where demand doesn’t exist, don’t provide it • I.e. 2am-5am

4. Different Viewpoints • 1) Management viewpoint • Minimize total cost • Costs: vehicle hours and miles • Travel varies by time of day, day of week, and time of year • In order to meet demand at peak times, excessive service may be necessary

5. Different Viewpoints • 1) Management viewpoint, cont • May be in best interest to discourage peak ridership • Not worth it to add vehicles and drivers for that short time • Possible disincentive: lower prices for off-peak times • Not worth it unless a total piece of work is eliminated

6. Different Viewpoints • 2) Driver Viewpoint • Want schedules that easy to meet, convenient layovers, short work days, and convenient starting times. • Need breaks and mealtimes during the day

7. Different Viewpoints • 2) Driver Viewpoint, cont • Labor contracts with drivers usually specify constraints • i.e. drivers working >10 hours/day need to be paid extra • Contract provision have a major effects on schedules, costs, spread penalties, layover provisions, split shifts, etc

8. Different Viewpoints • 3) Customer Viewpoint • Need to be at destination at given time, want to avoid waiting, want reliable service, schedules that are easy to remember, availability of service at all hours, weekends, holidays

9. Example of Transit Schedule

10. Application: Bob’s Job • Bob works in New York City at the School of the Future, near the 23rd and Park 6 train stop. • To save money, he lives in the Bronx. His closest subway station is the 1 train Van Cortlandt Park at 242nd and Broadway. • To maximize his utility, Bob would like to take at most 50 minutes to get to work.

11. Application, Cont • To get to work, Bob must start at Van Cortlandt, ride the 1 train to 42nd street, take the shuttle to Grand Central, then take the 6 train to 23rd. • We researched the headways for all three trains, and the transit times for these three rides.

12. Application, Cont • Flow shop application • Bob going to work is one job • Each platform and train is a machine • The processing times on each machine are sometimes stochastic and sometimes fixed • There is a fixed order • No machine can start without the prior completing

13. Application, Cont • 1 train at 242nd: expect to wait 0-7 mins • Ride to 42nd: expect to take 38-39 mins • Shuttle at 42nd: expect to wait 0-3 mins • Ride to Grand Central: expect to take 2 mins • 6 train at Grand Central: expect to wait 0-5 mins • Ride to 23rd: expect to take 4 mins

14. Application, Cont • We ran 100 trials by generating random numbers within the stochastic ranges • Compiled total transit times • Average: 52 minutes • Shortest transit: 45 minutes • Largest transit: 60 minutes

15. Application, Cont

16. Application, Cont • Is it worth it to add more trains in order to lower this 52 minute expected travel time to 50 minutes? • Only reduce waiting times at 242nd and GCT • Number of trains would need be increased • Congestion • Monetary concern • Ran this simulation of decreasing headways to 5 minutes and 242nd, decreased total transit by less than 2 minutes

17. Application, Cont • Conclusion • Not worth money • Congestion may cause transit time to increase even more