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.

Photo: Getty
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In focusing on the famous few, we risk doing a disservice to all victims of child sexual abuse

There is a danger that we make it harder, not easier, for victims to come forward in future. 

Back in the 1970s when relations between journalists and police were somewhat different to today a simple ritual would be carried out around the country at various times throughout the week.

Reporters, eager for information for their regional newspaper, would take a trip to the local station and there would be met by a desk sergeant who would helpfully skim through details in the crime Incident Book.

Among the entries about petty thefts, burglaries and road accidents there would occasionally be a reference to an allegation of incest. And at this point the sergeant and journalist might well screw-up their faces, shake their heads and swiftly move on to the next log. The subject was basically taboo, seen as something ‘a bit mucky,’ not what was wanted in a family newspaper.

And that’s really the way things stayed until 1986 when ChildLine was set up by Dame Esther Rantzen in the wake of a BBC programme about child abuse. For the first time children felt able to speak out about being sexually assaulted by the very adults whose role in life was to protect them.

And for the first time the picture became clear about what incest really meant in many cases. It wasn’t simply a low level crime to be swept under the carpet in case it scratched people’s sensitivities. It frequently involved children being abused by members of their close family, repeatedly, over many years.

Slowly but surely as the years rolled on the NSPCC continued to press the message about the prevalence of child sexual abuse, while encouraging victims to come forward. During this time the corrosive effects of this most insidious crime have been painfully detailed by many of those whose lives have been derailed by it. And of course the details of the hundreds of opportunistic sexual assaults committed by Jimmy Savile have been indelibly branded onto the nation’s consciousness.

It’s been a long road - particularly for those who were raped or otherwise abused as children and are now well into their later years - to bring society around to accepting that this is not to be treated as a dark secret that we really don’t want to expose to daylight. Many of those who called our helpline during the early days of the Savile investigation had never told anyone about the traumatic events of their childhoods despite the fact they had reached retirement age.

So, having buried the taboo, we seem to be in danger of giving it the kiss of life with the way some cases of alleged abuse are now being perceived.

It’s quite right that all claims of sexual assault should be investigated, tested and, where there is a case, pursued through the judicial system. No one is above the law, whether a ‘celebrity’ or a lord.

But we seem to have lost a sense of perspective when it comes to these crimes with vast resources being allocated to a handful of cases while many thousands of reported incidents are virtually on hold.

The police should never have to apologise for investigating crimes and following leads. However, if allegations are false or cannot be substantiated they should say so. This would be a strength not a weakness.

It is, of course, difficult that in many of the high-profile cases of recent times the identities of those under investigation have not been officially released by the police but have come to light through other means. Yet we have to deal with the world as it is not as we wish it would be and once names are common knowledge the results of the investigations centring on them should be made public.

When it emerges that someone in the public eye is being investigated for non-recent child abuse it obviously stirs the interest of the media whose appetite can be insatiable. This puts pressure on the police who don’t want to repeat the mistakes of the past by allowing offenders to slip through their hands.  And so there is a danger, as has been seen in recent cases, that officers lack confidence in declaring there is a lack of evidence or the allegations are not true. 

The disproportionate weight of media attention given to say, Sir Edward Heath, as opposed to the Bradford grooming gang sentenced this week, shows there is a danger the pendulum is swinging too far the other way. This threatens the painstaking work invested in ensuring the public and our institutions recognise child abuse as a very real danger. 

Whilst high profile cases have helped the cause there is now a real risk that the all-encompassing focus on them does both victims of abuse and those advocating on their behalf a fundamental disservice.

As the public watches high -profile cases collapsing amidst a media fanfare genuine convictions made across the country week in week out go virtually unannounced. If this trend continues they may start to believe that child sexual abuse isn’t the prolific problem we know it to be.

So, while detectives peer into the mists of time, searching for long lost clues, we have to face the unpalatable possibility that offences being committed today will in turn only be investigated fully in years or decades' time because there is not the manpower to deal with them right now.

So, now the Goddard Inquiry is in full swing, taking evidence about allegations of child sex crimes involving ‘well known people’ as well as institutional abuse, how do we ensure we don’t fail today’s victims?

If they start to think their stories are going to be diminished by the continuing furore over how some senior public figures have been treated by the police they will stay silent. Therefore we have to continue to encourage them to come forward, to give them the confidence of knowing they will be listened to.

If we don’t we will find ourselves back in those incestuous days where people conspired to say and do nothing to prevent child abuse.

Peter Wanless is Chief Executive of the NSPCC.