Transport planning is a tricky business. Can visualisation tools help?

Visualising London's bike share scheme. Image: Ito World.

Visualisation is a crucial tool in understanding and communicating data. Its use in transport planning is growing, but it remains a specialist activity, often reserved for larger, higher profile projects.

However, the arrival of new tools that focus on movement data make it quick and easy for anyone to visualise sensor and modelling data key to transport planning.

The use of data visualisation has exploded across a wide range of industries over the last decade, with the pace ever increasing. There has been a shift from analysing data using statistical techniques alone, as people adopt graphical representations to aid analysis and understanding.

The growth of business intelligence (BI) tools such as Tableau, Qlik View and Microsoft Power BI that provide advanced analytics and visualisation is a measure of this transformation. These tools leverage the brain’s capacity to quickly understand and interpret graphical rather than numerical representations.

Such tools are increasingly being used within transport planning, alongside traditional GIS software such as ArcGIS and MapInfo for handling geospatial data; and 3D modelling tools to generate photo realistic renderings of transport schemes. BI and GIS software provide powerful functionality to look at static data and simple representations of temporal data but they lack the capability to easily and effectively combine spatial and temporal elements into informative interactive visualisations.

Movement data

What if you could easily visualise this movement data? What would be the value to a transport project if you could easily analyse the data and communicate key metrics and findings? How do trip profiles change over time? How do traffic flow, speed, journey times or pollution levels vary throughout a network over an hour, week, month, year? And what is the impact of the scheme over five, 10 or 20 years?

Visualisation helps answer these questions. It provides clarity and facilitates discussion throughout a project, providing a means for everyone involved to understand the issues.

A selection of Ito World visualisations.

The use of interactive visualisation to present large complex datasets allows the viewer to comprehend and analyse data that would otherwise be impenetrable. You can quickly spot patterns, trends and anomalies that are difficult to identify when studied using numerical analytical tools alone. This is particularly apparent when dealing with movement data that varies by both time and location; for example, you can easily view trips by purpose, origin, destination, mode of transport or any combination, understanding how they vary over time.

Interactive visualisations exploit and enhance the viewer’s cognitive capabilities rather than relying on predefined numerical approaches. When both temporal and spatial dimensions can be easily and effectively presented simultaneously, visualisation becomes valuable at all stages of a transport project.

The ongoing transition to using large complex datasets automatically generated from sensors rather than traditional surveys to feed our transport models makes it more important than ever to understand the datasets being used. With the correct tools it becomes fast and easy to visually screen and validate this input data.


Visualisation is an effective tool for the calibration and validation of models as they are built. Model outputs can be visually compared against count data. While such visual inspection doesn’t replace statistical analysis, it can greatly accelerate the calibration phase by making it easier to spot inconsistencies, making iterations faster and reducing the number required.

Similarly, interactive visualisations of model output reveal insight during the analysis of results. Many leading traffic simulation software packages include visualisation capabilities for this purpose but others lack the functionality, as do custom developed spreadsheets, R or Python models.

Communicating findings

Effective visualisation is vital when communicating study results. Outputs from a range of analyses and models need to be communicated to stakeholders who are not necessarily experts in the use of a particular technique and are not used to looking at such outputs. Results need to be shared between sub-teams working on a project such as transport, economic and environmental teams; with project managers; project sponsors; and, in some cases, with ministers and the public.

The ability to convey complex information in a concise and understandable way is crucial for a project to progress. An effective visualisation can summarise a two hundred page report into a two minute video. It can set out the issues, and present and quantify the benefits of the solution in a way that non-experts can understand.

A key component of a successful visualisation is the ability to present different datasets in a common visual language. Consider the case of a new road scheme where a report may include historical and projected traffic data for the base case and different schemes; accident data; noise and air quality data; journey time predictions; as well as contextual information. These come from multiple sources, both measured and modelled, in a range of data formats.

The report is much easier for both the expert and non-expert audience to understand if all this information is presented in a consistent style, rather than varying according to the software package used to produce or analyse the data. The images below illustrates different datasets presented in a common visual language.

Click to expand. Image: Ito World.

Ultimately, with the right tools that focus on movement data, visualisation will be used throughout transport projects – saving time, increasing insight and delivering a better result for the end client. 

Johan Herrlin is the chief executive of Ito World.

 
 
 
 

Where actually is South London?

TFW Stephen Bush tells you that Chelsea is a South London team. Image: Getty.

To the casual observer, this may not seem like a particularly contentious question: isn’t it just everything ‘under’ the Thames when you look at the map? But despite this, some people will insist that places like Fulham, clearly north of the river, are in South London. Why?

Here are nine ways of defining South London.

The Thames

Image: Google Maps/CityMetric.

It’s a curvy river, the Thames. Hampton Court Palace, which is on the north bank of the river, is miles south of the London Eye, on the south bank. If the river forms a hard border between North and South Londons, then logically sometimes North London is going to be south of South London, which is, to be fair, confusing. But how else could we do it?

Latitude

You could just draw a horizontal line across a central point (say, Charing Cross, where the road distances are measured from). While this solves the London Eye/Hampton Court problem, this puts Thamesmead in North London, and Shepherd’s Bush in South London, which doesn’t seem right either.

Image: Google Maps/CityMetric.

And if you tried to use longitude to define West and East London on top of this, nothing would ever make sense ever again.

The Post Office

Image: Wikimedia Commons.

Some people give the Post Office the deciding vote, arguing that North and South London are defined by their postcodes. This does have some advantages, such as removing many contentious areas from the debate because they’re either in the West, East or Central postcode divisions, or ignoring Croydon.

But six of the SW postcodes are north of the river Thames, so we’re back to saying places like Fulham and Chelsea are in south London. Which is apparently fine with some people, but are we also going to concede that Big Ben and Buckingham Palace are South London landmarks?

Taken to the extreme this argument denies that South London exists at all. The South postcode region was abolished in 1868, to be merged into the SE and SW regions. The S postcode area is now Sheffield. So is Sheffield in South London, postcode truthers? Is that what you want?

Transport for London

Image: TfL.

At first glance TfL might not appear to have anything to add to the debate. The transport zones are about distance from the centre rather than compass point. And the Northern Line runs all the way through both North and South London, so maybe they’re just confused about the entire concept of directions.

 

Image: TfL.

But their website does provide bus maps that divide the city into 5 regions: North East, South East, South West, North West and the Centre. Although this unusual approach is roughly speaking achieved by drawing lines across and down the middle, then a box around the central London, there are some inconsistencies. Parts of Fulham are called for the South West region, yet the whole of the Isle of Dogs is now in North East London? Sick. It’s sick.

The Boundary Commission

One group of people who ought to know a thing or two about boundaries is the Boundary Commission for England. When coming up with proposals for reforming parliamentary constituencies in 2011, it first had to define ‘sub-regions’ for London.

Initially it suggested three – South, North East, and a combined North, West and Central region, which included Richmond (controversial!) – before merging the latter two into ‘North’ and shifting Richmond back to the South.

In the most recent proposal the regions have reverted to North Thames and South Thames (splitting Richmond), landing us right back where we started. Thanks a bunch, boundary commission.

The London Plan

Image: Greater London Authority.

What does the Mayor of London have to say? His office issues a London Plan, which divides London into five parts. Currently ‘South’ includes only Bromley, Croydon, Kingston upon Thames, Merton, Sutton, and Wandsworth, while the ‘North’ consists of just Barnet, Enfield, and Haringey. Everywhere else is divvied into East, South or Central.

While this minimalist approach does have the appeal of satisfying no-one, given the scheme has been completely revised twice since 2004 it does carry the risk of seismic upheaval. What if Sadiq gets drunk on power and declares that Islington is in East London? What then?

Wikipedia

 

Image: Wikimedia Commons/CityMetric.

The coordinates listed on the South London article lead to Brockwell Park near Herne Hill, while the coordinates on the North London article lead to a garden centre near Redbridge. I don’t know what this means, so I tried to ring the garden centre to see if they had any advice on the matter. It was closed.

Pevsner Guides

Image: Wikimedia Commons/CityMetric.

Art historian Sir Nikolaus Pevsner might seem an unlikely source of help at this juncture, but we’ve tried everything else. And the series of architectural guides that he edited, The Buildings of England, originally included 2 volumes for London: “The Cities of London and Westminster”, and “everything else”. Which is useless.

But as his successors have revised his work, London has expanded to fill 6 volumes: North, North West, East, The City, Westminster, and South. South, quite sensibly, includes every borough south of the Thames, and any borough that is partly south of the Thames (i.e. Richmond). And as a bonus: West London no longer exists.

McDonald’s

I rang a McDonald’s in Fulham and asked if they were in South London. They said no.

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