Harry Beck's 1933 Tube map. Image: Transport for London
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Using the science of peripheral vision to test the Tube map

We know how the brain processes things on the edge of its field of vision, and we can use that to analyse the quality of subway maps.

Cartography is a demanding technical skill. The best maps, those that define their subjects, can become icons of design in themselves. London’s Tube map is one of these - so much so, that it’s rare when a major city’s subway network doesn’t look to TfL’s map for inspiration.

The story goes that London Underground was sceptical of Harry Beck’s Tube map, and only produced a small run of pamphlets featuring it in 1932 as an experiment. Its immediate popularity proved that Beck’s insight - which seemed counter-intuitive to many people at London Underground - was correct. When trying to get between stations all you want is the relationship between them, not the geography above ground.

But how to represent that relationship? Beck looked to circuit diagrams, connecting stations with lines that were strictly at 90- and 45-degree angles. No curves. Ticks and diamonds (now ticks and circles) for stations and interchanges. Compared to the horror of, say, New York City’s subway map, it feels clean, and instantly comprehensible at a glance.

That’s an important thing for a subway map - people will be in situations where they need to check where they are in their journey with only a brief look, often out of the corner of their eye, while standing up in a crowded space or reacting to news from the driver of delays on another line. Sure, when entering a station there's more time to pause, gaze, and absorb, but the key to a good subway map is simple: the greatest amount of information in the shortest amount of time.

At MIT, Ruth Rosenholtz and her team from the Department of Brain and Cognitive Sciences have been working on how much humans can comprehend through peripheral vision. MIT’s in Boston, and the city recently held a competition to design a new subway map. Here’s the existing one (click images to expand):

And here’s the contest winner, submitted by Russian designer Mikheil Kvrivishvili:

There’s something about the second one that’s just better, isn’t there? But how to tell exactly what that is?

Research into peripheral vision has shown that the brain's comprehension of things outside of the point of focus is muddled. Our brains do a good job of fooling us that we have a larger field of vision than we actually have, but if you’re looking at a specific station on a subway map, information that’s further away from it gets distorted - it's a vague impression of colour and shape, but nothing more.

Rosenholtz and her team have created visualisations they call “mongrels” that simulate what the brain actually sees when it looks at a map, as a way of verifying the quality of a map’s design. The better the map, the less information gets lost in the mongrelisation. It's as close as you can get to a snapshot of what humans truly see when they glance at a map in the setting of a subway train.

Here’s the mongrel for Boston’s existing map, for someone who's focusing on the Kendall/MIT stop on the red line:

And here’s the mongrel for the map contest winner, focused on the same station:

Now it's possible to see why the new map is better. The silver line fades into the white background in both, which isn’t great, but the parallel layout of the lines and the greater space between station names makes it possible to still work out the structure of the system without everything washing out. Simply put, at a glance, the second map always gives you the full system and your place within it, and the first one doesn't.

I emailed Rosenholtz about these maps, and she and her team very kindly produced a similar mongrelisation of the Tube map for us. Here it is:

Turns out, it’s not too bad! It’s centred on Oxford Circus, and everything around it out to the Circle line and beyond, along the lines that have been around for decades, looks pretty good. It's a much bigger network than Boston's so everything is necessarily a bit smaller, but that's unavoidable.

The problem areas look to be the newer additions to the network - the DLR is a mess, and the Overground doesn’t really stand out. In 2015, as the first phase of Crossrail goes into action and TfL takes over the commuter rail lines running through Hackney, that bit of the map is going to look even more complicated and could become more of a mess (and transport blogger Diamond Geezer’s post on this is quite good on this). The Tube map has had things added to it over the years around the edges without the central section really being tweaked in kind, and it might be time to consider rejigging things in the middle to make more space for the outer lines.

But still, it’s still nice to know that, even though Beck’s map turned 81 this year, its initial assumptions about map design were right on the nose.

Ian Steadman is a staff science and technology writer at the New Statesman. He is on Twitter as @iansteadman.

European People's Party via Creative Commons
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Ansbach puts Europe's bravest politician under pressure

Angela Merkel must respond to a series of tragedies and criticisms of her refugee policy. 

Angela Merkel, the Chancellor of Germany, is supposed to be on holiday. Two separate attacks have put an end to that. The first, a mass shooting in Munich, was at first widely believed to be a terrorist attack, but later turned out to be the actions of a loner obsessed with US high school shootings. The second, where a man blew himself up in the town of Ansbach, caused less physical damage - three were seriously injured, but none killed. Nevertheless, this event may prove to affect even more people's lives. Because that man had come to Germany claiming to be a Syrian refugee. 

The attack came hours after a Syrian refugee murdered a pregnant Polish woman, a co-woker in a snack bar, in Reutlingen. All eyes will now be on Merkel who, more than any other European politician, is held responsible for Syrian refugees in Europe.

In 2015, when other European states were erecting barriers to keep out the million migrants and refugees marching north, Merkel kept Germany's borders open. The country has resettled 41,899 Syrians since 2013, according to the UNHCR, of which 20,067 came on humanitarian grounds and 21,832 through private sponsorship. That is twice as much as the UK has pledged to resettle by 2020. The actual number of Syrians in Germany is far higher - 90 per cent of the 102,400 Syrians applying for EU asylum in the first quarter of 2016 were registered there. 

Merkel is the bravest of Europe's politicians. Contrary to some assertions on the right, she did not invent the refugee crisis. Five years of brutal war in Syria did that. Merkel was simply the first of the continent's most prominent leaders to stop ignoring it. If Germany had not absorbed so many refugees, they would still be in central Europe and the Balkans, and we would be seeing even more pictures of starved children in informal camps than we do today. 

Equally, the problems facing Merkel now are not hers alone. These are the problems facing all of Europe's major states, whether or not they recognise them. 

Take the failed Syrian asylum seeker of Ansbach (his application was rejected but he could not be deported back to a warzone). In Germany, his application could at least be considered, and rejected. Europe as a whole has not invested in the processing centres required to determine who is a Syrian civilian, who might be a Syrian combatant and who is simply taking advantage of the black market in Syrian passports to masquerade as a refugee. 

Secondly, there is the subject of trauma. The Munich shooter appears to have had no links to Islamic State or Syria, but his act underlines the fact you do not need a grand political narrative to inflict hurt on others. Syrians who have experienced unspeakable violence either in their homeland or en route to Europe are left psychologically damaged. That is not to suggest they will turn to violence. But it is still safer to offer such people therapy than leave them to drift around Europe, unmonitored and unsupported, as other countries seem willing to do. 

Third, there is the question of lawlessness. Syrians have been blamed for everything from the Cologne attacks in January to creeping Islamist radicalisation. But apart from the fact that these reports can turn out to be overblown (two of the 58 men arrested over Cologne were Syrians), it is unclear what the alternative would be. Policies that force Syrians underground have already greatly empowered Europe's network of human traffickers and thugs.

So far, Merkel seems to be standing her ground. Her home affairs spokesman, Stephan Mayer, told the BBC that Germany had room to improve on its asylum policy, but stressed each attack was different. 

He said: "Horrible things take place in Syria. And it is the biggest humanitarian catastrophe, so it is completely wrong to blame Angela Merkel, or her refugee policies, for these incidents." Many will do, all the same.