Source code: github.com/npct/pct/ 2017-08-24

Contents

  • Introduction: the Propensity to Cycle Tool
  • The impacts of transport infrastructure
  • Methods
  • Results and discussion

Introduction

The Propensity to Cycle Tool - see www.pct.bike

The front page of the open source, open access Propensity to Cycle Tool (PCT).

The front page of the open source, open access Propensity to Cycle Tool (PCT).

Prior work (source: Lovelace et al. 2017)

Tool Scale Coverage Public access Format of output Levels of analysis Software licence
Propensity to Cycle Tool National England Yes Online map A, OD, R, RN Open source
Prioritization Index City Montreal No GIS-based P, A, R Proprietary
PAT Local Parts of Dublin No GIS-based A, OD, R Proprietary
Usage intensity index City Belo Horizonte No GIS-based A, OD, R, I Proprietary
Bicycle share model National England, Wales No Static A, R Unknown
Cycling Potential Tool City London No Static A, I Unknown
Santa Monica model City Santa Monica No Static P, OD, A Unknown

The PCT team

"If you want to go far, go as a team"

Robin Lovelace (Lead Developer, University of Leeds)

  • James Woodcock (Principal Investigator, Cambridge University)
  • Anna Goodman (Lead Data Analyst, LSHTM)
  • Rachel Aldred (Lead Policy and Practice, Westminster University)
  • Ali Abbas (User Interface, University of Cambridge)
  • Alvaro Ullrich (Data Management, University of Cambridge)
  • Nikolai Berkoff (System Architecture, Independent Developer)
  • Malcolm Morgan (GIS and infrastructure expert, UoL)

Policy feedback

"The PCT is a brilliant example of using Big Data to better plan infrastructure investment. It will allow us to have more confidence that new schemes are built in places and along travel corridors where there is high latent demand."

  • Shane Snow: Head of Seamless Travel Team, Sustainable and Acessible Travel Division

"The PCT shows the country’s great potential to get on their bikes, highlights the areas of highest possible growth and will be a useful innovation for local authorities to get the greatest bang for their buck from cycling investments  and realise cycling potential."

  • Andrew Jones, Parliamentary Under Secretary of State for Transport

The PCT in CWIS and LCWIP

Included in Cycling and Walking Infrastructure Strategy (CWIS) and the Local Cycling and Walking Infrastructure Plan (LCWIP)

How the PCT works

Shows on the map where there is high cycling potential, for 4 scenarios of change

  • Government Target
  • Gender Equality
  • Go Dutch
  • Ebikes

Scenario shift in desire lines

Source: Lovelace et al. (2017)

  • Origin-destination data shows 'desire lines'
  • How will these shift with cycling uptake

Scenario shift in network load

The impacts of transport infrastructure

The impacts of transport infrastructre

Credit: flickr user thestuff, Creative Commons Licence

Research into impacts of roads

The extension of the M74 motorway = 'natural experiment':

  • People who live near motorways seem to be less physically active (D. Ogilvie et al. 2006)
  • And more car dependent (Prins et al. 2017)
    • Although no evidence of impacts on active travel

Research into impacts of roads II

A recent review of impact assessment methods in the English context found that an increasingly wide range of methods and approaches were being used (Tajima and Fischer 2013):

  • Environmental Impact Assessment (EIA)
  • Strategic Environmental Assessment (SEA)
  • Health Impact Assessment (HIA)
  • Gender Impact Assessment (GIA)
  • Equality Impact Assessment (EqIA)

  • But overall not a huge amount of research in the area, particularly in relation to the impact on active travel:

  • "there is very little empirical data on the impact of road transport interventions", aside from injury reduction estimates (Thomson et al. 2008)

Active travel impacts: a typology

A typology of active travel options.

A typology of active travel options.

Methods

The study area

Parallels (Credit: Philip McErlean, CC )

Cycling potential parallel to the route

3 stage methodology to identify parallel lines:

  • Subset desire lines whose cetrepoints are far from the proposed route
  • Segment the proposed route
  • Calculate the angle of each route

Then keep only lines parallel to proposed route segments

Subsetting desire lines by centre point proximity

Finding desire lines that are (roughly) parallel

This involved the development of a new R function:

The angle_diff function

From the R package stplanr

## function (l, angle, bidirectional = FALSE, absolute = TRUE) 
## {
##     if (is(object = l, "Spatial")) {
##         line_angles = line_bearing(l)
##     }
##     else {
##         line_angles = l
##     }
##     angle_diff = angle - line_angles
##     angle_diff[angle_diff <= -180] = angle_diff[angle_diff <= 
##         -180] + 180
##     angle_diff[angle_diff >= 180] = angle_diff[angle_diff >= 
##         180] - 180
##     if (bidirectional) {
##         angle_diff[angle_diff <= -90] = 180 + angle_diff[angle_diff <= 
##             -90]
##         angle_diff[angle_diff >= 90] = 180 - angle_diff[angle_diff >= 
##             90]
##     }
##     if (absolute) 
##         angle_diff = abs(angle_diff)
##     angle_diff
## }
## <bytecode: 0xfb68578>
## <environment: namespace:stplanr>

What about perpendicular lines (severance)?

The same method!

3: Access to stations (Credit: M. Morgan)

  • Divide each route into 3

How to deal with long, windy routes?

  • Break the train line into segments
Method of splitting the route into discrete segments using the line segment function from the stplanr R package (a) and cycling potential severed (b).

Method of splitting the route into discrete segments using the line segment function from the stplanr R package (a) and cycling potential severed (b).

All methods together

Centre point-buffer (a), parallel (b), perpendicular (c) and station access (d) methods.

Centre point-buffer (a), parallel (b), perpendicular (c) and station access (d) methods.

Results and discussion

Cycling opportunities and threats

Scenario N. commuters N. cycling % cycling Distance (km, Euclidean)
Baseline
Touching buffer 53665 1537 2.9 11.9
Parallel selection 2583 28 1.1 13
Perpendicular selection 1678 21 1.3 18.5
Cycling to stations 574 3 0.5 17.9
Scenario
Touching buffer 53665 2568 4.8 11.9
Parallel selection 2583 61 2.4 13
Perpendicular selection 1678 36 2.2 18.5
Cycling to stations 574 49.5 8.6 2.6

Final question

  • How to integrate this work in existing tools?
  • How to ensure maximum policy impact?
  • How reproducibility can help?

Thanks + References

  • Thanks for listening - get in touch via r.lovelace@leeds.ac.uk or @robinlovelace

Lovelace, Robin, Anna Goodman, Rachel Aldred, Nikolai Berkoff, Ali Abbas, and James Woodcock. 2017. “The Propensity to Cycle Tool: An Open Source Online System for Sustainable Transport Planning.” Journal of Transport and Land Use, December. doi:10.5198/jtlu.2016.862.

Ogilvie, David, Richard Mitchell, Nanette Mutrie, Mark Petticrew, and Stephen Platt. 2006. “Evaluating Health Effects of Transport Interventions: Methodologic Case Study.” American Journal of Preventive Medicine 31 (2): 118–26. doi:10.1016/j.amepre.2006.03.030.

Prins, R. G., L. Foley, N. Mutrie, D. B. Ogilvie, and M74 study team. 2017. “Effects of Urban Motorways on Physical Activity and Sedentary Behaviour in Local Residents: A Natural Experimental Study.” The International Journal of Behavioral Nutrition and Physical Activity 14 (1): 102. doi:10.1186/s12966-017-0557-0.

Tajima, Ryo, and Thomas B Fischer. 2013. “Should Different Impact Assessment Instruments Be Integrated? Evidence from English Spatial Planning.” Environmental Impact Assessment Review 41: 29–37.

Thomson, Hilary, Ruth Jepson, Fintan Hurley, and Margaret Douglas. 2008. “Assessing the Unintended Health Impacts of Road Transport Policies and Interventions: Translating Research Evidence for Use in Policy and Practice.” BMC Public Health 8: 339. doi:10.1186/1471-2458-8-339.