LLITM Public Transport Supply Model

Transcription

1 LLITM Public Transport Supply Model Paul Smith 11 th May 2011 Leicestershire County Council

2 Public Transport in Leicestershire Sustainable transport moving from an abstract concept to necessity PT modes are instrumental in delivering sustainability within the local policy agenda. Need to demonstrate efficiency of schemes from various perspectives - Economic - Financial - Operational Within LLITM comprehensive tool is required to inform on PT issues. 2

3 Our Brief 1 Public Transport Model with demand derived from new data collection (2008) and existing models Using client specified software Zone system defined by client Full coverage of PT services operating within, to/from the county Bus stopping locations and stopping patterns to be accurately specified Coding to be congruent with SATURN Highway Model Calibration to timetable times Relationship between highway speeds and bus speeds Logical set of screenlines for calibration / validation Calibration and validation 1: ACS LLITM Brief, 29 th September

4 Responsibilities - All supply network related development - Negotiation for supply of LENNON (rail data) used for both supply side and demand side elements - Provision of travel cost data to assist demand development - Calibration and validation of supply models - Development of prior demand matrices - Application of model for forecast purposes 4

5 Main Tasks Design and Supervision of Data Collection Data Processing Network Coding Assistance with demand development Calibration Validation Support to other workstreams 5

6 Model Characteristics - 1 Model informs on complex choices based on: Travel by service and corridor Multi routing between origin-destinations Sub-Mode choice Boarding location Interchange location Alighting node Fare levels Model necessitates simplification by User classes Cost feedback (crowding) 6

7 Model Characteristics - 2 Software: CUBE VOYAGER 5 Model base: 2008 Time Periods: AM (8:00-9:00), IP (average between 10:00 and 16:00) and PM (17:00-18:00) Single User Class (all pax) Zones as per highway Multimodal assignment (bus, coach, rail, walk access) Coverage: - All public scheduled local bus, coach, rail services. - Excludes school services - Excludes infrequent services of headway >120 mins (such as single day only services), except for access. 7

8 Model Development - 1 Bus Network - City and County coverage - Routes including stops - AM/PM/IP travel time from 2008 timetables - AM/PM/IP frequency from 2008 timetables - Specified as unitary vehicle type. 25 operators represented, including: - First Leicester; - Arriva; - Kinch Bus; - Stagecoach; - Paul James; -etc 8

9 Local Bus Local Bus in Leicestershire Local Bus in Leicester City 9

10 County Express Bus and National Express Coach National Express Coach Express Bus and Coach in Leicestershire 10

11 Model Development - 2 Rail Services - Coverage focussed on East Midland Trains Network and Cross Country Birmingham - Stansted - Midland Main Line Services through Leicestershire and local services to and from Leicester - Inclusion of other franchisees to ensure appropriate coverage: West Coast Main Line - Interface at Nuneaton London Midland and Virgin West Coast East Coast Main Line Interface at Grantham, Peterborough NXEC 11

12 National Rail National Rail Network East Midland Rail Network 12

13 Network Development CUBE Network Structure developed from - SATURN Highway Network - ATCO Cif File public transport data - Rail Alignment Data (National Rail) Base Year speeds derived from timetable data Bus lane and bus only link/turn data included Line coding: - Systematic approach using Coding Manual (Mode, operator, fares etc) Mindful of assignment procedures: - Multi routing procedure using service frequency and cost model 13

14 Walk Links Walk links from zone to stop developed automatically refined by hand Range and threshold defines preparedness to travel to particular stops Adjustments reflect natural routes and barriers Bus rail interchange links added Bus to bus interchange links added but scaled back due to software performance issues 14

15 Fares Bus fares developed using fare tables from selected major operators Distance based structure developed as a proxy for fare stages Downlift to reflect concessionary proportions (excluding half fares) Rail fares based on LENNON ticket sales, includes all ORCATS related sales. Excludes operator specific and PTE tickets. 15

16 Parameters No Stated Preference undertaken. All supply model values off the shelf Transit time function developed based on observed relationship between highway and bus based PT Decision to use transit time over timetable time dependent upon circumstance Values of time consistent with WebTAG. Refresh is imminent Component cost weightings not empirically derived. Developed from indicative values. Model was insensitive to variations in indicative values, Hence, relative to IVT - Wait time x Walk time x Interchange penalty + 8 mins (plus potential walk, subsequent wait) Wait curves to reflect timed arrival for infrequent services. Short (bus) and long (rail) wait variants 16

17 Demand Development Three components: - Observed bus demand from Origin Destination Interview sites, Market towns and Leicester - Observed rail demand from LENNON ticketing data - Synthetic demand based on trip-end estimates, observed matrices and costs from the public transport assignment Most PT demand is focussed on movements to/from urban centres Public transport legs of specific mixed mode trips (Park and Ride) 17

18 Assignment Multi-Step process Based on Generalised costs (weighted by coefficients) Enumeration of routes. - Origin to Destination - Simple trips with short walk distances - Multirouting Evaluation of probability of using route - Works back from destination - Logit choice models for walk & alternative alighting In LLITM Service Frequency Cost Model is employed - Assumes knowledge of travel time to destination (timetable knowledge) - Less use of slower routes with higher frequency. Loading of demand according to probabilities Retention of path files Skimming of cost components 18

19 Calibration Data from LTP Monitoring Sites - 1 City Centre Screenline Outer Ring Road Screenline 19

20 Calibration Data from LTP Monitoring Sites - 2 North South County Screenline Data taken from LTP monitoring data undertaken by Leicester City Information is available year by year Anomalous data investigated to provide higher confidence 20

21 Matrix Estimation Methods Use of CUBE Analyst Based on maximum entropy methods Uses variety of data items with ascribed relative confidences Constraints are matched where possible Route choice file from initial assignments is employed No constraint is placed on trip ends as confidence in PT trip rates is lower than for highway model 21

22 Model Calibration WebTAG does not specify calibration requirements Nevertheless model is generally within an 85% threshold of observed Model within confidence intervals, as defined by quality of counts GEH proximity is for information only Rail calibration (at key Leicestershire Stations) is within 5% for all sites/time periods General message is that of a close representation of observed flows Criteria Flow Test? CI range? GEH<10? GEH<5? AM Sites 84% 77% 100% 97% AM Screenlines 90% 100% 100% 90% IP Sites 86% 86% 100% 100% IP Screenlines 100% 86% 100% 100% PM Sites 85% 85% 100% 98% PM Screenlines 100% 100% 100% 100% 22

23 Matrix Calibration Changes 6,000 5,000 AM Peak Period Bus and Coach Transit Trip Length Distribution Pre Trips Post Trips 4,000 3,000 2,000 1, Trips 0 to 5 5 to to to to to to to to to to to to to to to to 85 Distance (km) 5,000 4,500 IP Peak Period Bus and Coach Transit Trip Length Pre Trips Post Trips 4,000 3,500 3,000 2,500 2,000 1,500 1, Trips 0 to 5 5 to to to to to to to to to to to to to to to to 85 Distance (km) 4,500 4,000 PM Peak Period Bus and Coach Transit Trip Length Distribution Pre Trips Post Trips 3,500 3,000 2,500 2,000 1,500 1, Trips 0 to 5 5 to to to to to to to to to to to to to to to to 85 Distance (km) Overall matrix totals do not change Change is concentrated in LCC Reductions of up to 56% in the observed data to match constraints Greatest overall adjustment in the PM peak

24 Model Validation - 1 Observed data derived from varied sources Stop boardings and alightings - not truly independent as information used in matrix build Overall close proximity for PT model, albeit some passes are based on low volume criteria Stop Area AM %Diff Pass? IP %Diff Pass? PM %Diff Pass? Leicester -4.80% 4.00% 4.20% Stop Group A 30.20% 12.00% 6.60% Stop Group B 1.30% % 16.90% Stop Group C -8.20% 10.10% 4.60% Stop Group E -7.90% -4.50% -3.90% Stop Group S 0.50% 62.50% 38.10% Stop Group P 8.00% -0.20% -8.80% Stop Group R 61.80% 25.30% 16.70% Stop Group W % 8.50% 0.30% Loughborough 2.20% % 11.00% Melton Mowbray % -8.50% 63.80% Mkt Harborough % % % Hinckley % % -3.20% Ashby-de-la-Zouch % 11.30% % Lutterworth -0.30% % % 24

25 Model Validation - 2 Congestion Monitoring Routes from LTP Two cordons identified. AM inbound only Upper 95% Lower 95% Section Obsv CI CI Mod M/O GEH diff %Diff Pass? Checketts Road - Loughborough Road % Corporation Road - Blackbird Road % Scraptoft Lane - Coleman Road % Knighton Road - Victoria Park Road % Knighton Lane East - Aylestone Road % Glenhills Way - Wigston Lane % Fosse Park Avenue - Braunstone Lane % New Parks Way - Cort Crescent % Glenfrith Way - Blackbird Road % Cordon 1 Total % Humberstone Road - Troon Way % Red Hill Circle - Corporation Road % Sturdee Road - Glenhills Boulevard % Spencefield Lane - Colchester Road % Blaby Bypass - Glenhills W ay % A46 Roundabout - Gynsills Lane % Beggars Lane - Kirby Lane % The Parade, Oadby - A563 Roundabout % Cordon 2 Total % 3% for inner cordon 5% for outer cordon Overall close proximity 25

26 Model Validation - 3 Boardings in LTP area Developed from expansion of modelled time periods Close correlation Number Observed Modelled GEH Absolute Difference Percentage Difference Daily Boardings - LTP Area 98, , % Peak boardings - LTP Area 25,702 26, % 26

27 Forecast Application Schemes to be reflected, e.g. new modes Requirements of Highway Model Review of walk link coding Impact on travel costs Level of detail within local area Application of congested travel times and delay to buses Review of patronage volumes and levels of service 27

28 Reporting Available Aggregate Boardings Link loadings Line loadings Line volume to capacity information Stop usage Mode choice % Selected link / line analyses Travel cost component analyses 28

29 Way Forward Way Forward - Strategic model.. - Local cali/vali might be required - Detailed coding might be required -Team of maintenance consultants to deal with this Suggested Updates - Additional outbound calibration data - Focus on Market Towns - Crowding could be beneficial - CUBE 6 software enhancements 29

30 Conclusions LLITM forms a strategic PT model covering a wide area It informs the larger suite of LLITM models via PT costs Through iteration with the demand team, a set of prior matrices was developed Performance of the calibration - validation is excellent and meets WebTAG recommendations Forecast years are being produced, these might highlight issues which could need investigation The model may require local calibration/validation and improvements for specific uses Software updates to CUBE 6 have resolved issues, which may impact on calibration - validation 30

31 Any Questions? 11 th May 2011 Leicestershire County Council