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User interface design and road planning - Deliberate ambiguity

Riding in his green Saab, we glide into Drachten, a 17th-century village that has grown into a bustling town of more than 40,000. We pass by the performing arts center, and suddenly, there it is: the Intersection. It's the confluence of two busy two-lane roads that handle 20,000 cars a day, plus thousands of bicyclists and pedestrians. Several years ago, Monderman ripped out all the traditional instruments used by traffic engineers to influence driver behavior - traffic lights, road markings, and some pedestrian crossings - and in their place created a roundabout, or traffic circle. The circle is remarkable for what it doesn't contain: signs or signals telling drivers how fast to go, who has the right-of-way, or how to behave. There are no lane markers or curbs separating street and sidewalk, so it's unclear exactly where the car zone ends and the pedestrian zone begins. To an approaching driver, the intersection is utterly ambiguous - and that's the point.

Monderman and I stand in silence by the side of the road a few minutes, watching the stream of motorists, cyclists, and pedestrians make their way through the circle, a giant concrete mixing bowl of transport. Somehow it all works. The drivers slow to gauge the intentions of crossing bicyclists and walkers. Negotiations over right-of-way are made through fleeting eye contact. Remarkably, traffic moves smoothly around the circle with hardly a brake screeching, horn honking, or obscene gesture. "I love it!" Monderman says at last. "Pedestrians and cyclists used to avoid this place, but now, as you see, the cars look out for the cyclists, the cyclists look out for the pedestrians, and everyone looks out for each other. You can't expect traffic signs and street markings to encourage that sort of behavior. You have to build it into the design of the road."

It's no surprise that the Dutch, a people renowned for social experimentation in practically every facet of life, have embraced new ideas in traffic management. But variations of Monderman's less-is-more approach to traffic engineering are spreading around the globe, showing up in Austria, Denmark, France, Germany, Spain, Sweden, the UK, and the US.

The rest:
http://www.wired.com/wired/archive/12.12/traffic_pr.html
Simon Tzu Send private email
Tuesday, December 07, 2004
 
 
That's really funny because I was hit by a car while walking through a roundabout.  The guy was going to the left when, as everyone knows, everyone going around the roundabout goes right.

And this was WITH a sign.

And here's another example:

There is a ring road around my university.  Where the ring completes it intersects an inroad.  Obviouvsly, those going around the ring should yeild to the influx on the inroad.  Nope.  Traffic accidents galore.

(By the way, in the case of the university, they went to a sign, a blinking light, and rumble strips and there were still accidents.  Go figure.)

When left to their own devices people are stupid.  Let's face it, even with instructions people are stupid.  Ambiguity leads to confusion, which leads to mistakes, which leads to accidents.

Just imagine if you used an application where all the icons were the same?

Nope, I don't think ambiguous interface design is a very good idea.
~ Send private email
Tuesday, December 07, 2004
 
 
Monderman obviously never drove in Boston.
Anony Coward
Tuesday, December 07, 2004
 
 
Boston is the worst.

It sounds like a fun experiment, but I have a question for you.

I'm an American in England and come upon an un-labeled roundabout. How do I know if I should go clockwise or counterclockwise?
www.MarkTAW.com Send private email
Tuesday, December 07, 2004
 
 
You look and slow down and look again and watch where the other cars are going. That's the point of all this; you're looking at the other cars, instead of at signs.
Nigel Send private email
Tuesday, December 07, 2004
 
 
And if there are no other cars? Okay, you can argue that the danger when there are no cars to me would be minimal for going the wrong direction, but what about that guy (you know the guy) who insists in driving as fast as physics will allow, and goes from being too far to see (or around a corner) to being dangerously close in the time it takes to look left, then right, then forward.
www.MarkTAW.com Send private email
Tuesday, December 07, 2004
 
 
In England people need to pass a driving test to be allowed to drive.  Preparation for this test includes learning about things like roundabouts.

Now as an American driving in Britain, I am sure you acquainted yourself first with our "Highway Code"?

Otherwise, you might be making all kinds of slipups, like driving on the wrong/right side of the road.
i like i
Wednesday, December 08, 2004
 
 
The wrong/right side of the road thing is obviously the point of my post. If Brits drive on the opposite side of the road, it makes sense that they go in the opposite direction on roundabouts. Studying traffic laws is one thing, remembering your paper learnings in a real life situation is another.

Okay, I've made my point, it's time to move on. It's not a particularly salient point anyway, and not worth this much space.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
Huh? Even a bear of very little brain could work it out. If you are approaching the roundabout on the left side of a road would you really expect to cut across traffic leaving the roundabout? If you do then you probably deserve what is coming to you (an articulated lorry).

Wednesday, December 08, 2004
 
 
We don't drive on the wrong side of the road! We drive on the correct side of the road! *WE* invented the idea of there being a correct side of the road to drive and we picked the side of the road to use.

In 1756 it was enacted as a city ordinance to solve the congestion problem on London Bridge. It became English and Scottish law in 1772.
Katie Lucas
Wednesday, December 08, 2004
 
 
What does logic have to do with driving? We don't drive by logic alone, we drive by instinct created by repetition. Haven't you ever gotten in to your car to go to one place, started driving to another by force of habit?

If my habit is to turn right at a roundabout, and I've turned right at roundabouts thousands of times in the past, despite any other logic, when faced with a non-labelled roundabout on a British road, I may - out of habit - turn right. It would probably be several days before I stop turning at regular intersections and landing on the right-hand side of the road.

I may also be extremely confused as my - by now ingrained - instincts tell me to do one thing, while I have to dig up the proper direction from deep within the recesses of my mind, or otherwise work out what the logical direction would be.

A non-labelled roundabout assumes everyone knows what to expect and do at a roundabout without much thought. All I'm doing is injecting a situation where the right ... err, correct thing could require quite a bit of thought. Even 5 seconds while driving could be disastrous. You could be looking around desperately for visual clues, and drift into a pedestrian or cyclist or car or even a stationary object like the statue at the center of the roundabout.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
Yup, the English drive on the correct side of the road - the only reason you drive on the wrong side is because of a Left Handed, FRENCH king (really, it is).
Mr Jack
Wednesday, December 08, 2004
 
 
Whichever country I'm in, I always drive down the middle of the road; saves an awful lot of indecision and thinking.
Mike Send private email
Wednesday, December 08, 2004
 
 
That sounds like a good strategy, but which way do you turn at roundabouts?
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
To be consistent, he could simply go over the middle.

Incidently Mark, the vast majority of English roundabouts are marked with sharp diversion boards which also indicate the direction of rotation.
Mr Jack
Wednesday, December 08, 2004
 
 
Monderman's point was that a roundabout is not obviously signed in order that everyone copes with them carefully. 

Your counterpoint was that you wouldn't.

Please - if you visit a country with different driving rules - drive safely, defensively and with minimum 'instinct'.  We would all like that you returned safely and continued posting here ;-)
i like i
Wednesday, December 08, 2004
 
 
Seriously, how many more people are not going to "get" the point of my post.

NOT HAVING SIGNS IS DISTRACTING.

It makes you have to think (or drive carefully as you say), and if you put too much thought into your driving, it means there's _something_ you're not paying attention to. So while you're looking for the signs, you're ignoring the pedestrians, or while you're looking for the pedestrians, you're ignoring the other cars. This isn't carelessness, it's fact. Confusion causes a sort of tunnel vision, and until you're comfortable again, you're likely to be missing something.

Mr. Jack - good point about obvious obstacles impeding you from turning on the wrong direction, thouth the article does imply that these things wouldn't exist as there are no sidewalks either.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
And I don't think his point was that people "cope" with not having signs, it's that not having signs is _better_ than having them. That signs turn people into worse drivers.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
> I'm an American in England and come upon an un-labeled roundabout. How do I know if I should go clockwise or counterclockwise?

You go clockwise. It's in the highway code (which is legally required reading) and it should be obvious because the road delivers you to the correct side of the circle; imagine you're driving north to a roundabout - the northbound lane is on the left, so the road delivers you to the western side of the roundabout. To go anticlockwise would require you to sharply turn out of the way. To go clockwise only requires you to go forward.
Steve Cooper Send private email
Wednesday, December 08, 2004
 
 
Sorry - part of the point of my post is that intrinsic to the roundabout's design, you are automatical delivered to the right part of the system; your momentum takes you in the right direction.

The lack of signs, then, is not so important as a straight cross-shaped intersection. The physical layout of the road takes you to the right place.
Steve Cooper Send private email
Wednesday, December 08, 2004
 
 
"but what about that guy (you know the guy) who insists in driving as fast as physics will allow"

Hey! How did I get dragged into this? :P

"If Brits drive on the opposite side of the road, it makes sense that they go in the opposite direction on roundabouts. "

Logic/instinct: The inner circle of a roundabout is the fast lane. The fast lane is the lane closest to oncoming traffic. The steering wheel is on the side of the car that's closest to oncoming traffic, so you can gauge your position on the road/overtake with more ease.

Conclusion: you drive on the roundabout in the direction that makes the driver's side of the car closest to the inner circle.

There is a point to all of this, you know.

"It would probably be several days before I stop turning at regular intersections and landing on the right-hand side of the road."

The fact that you're on the wrong side of the car helps.

"NOT HAVING SIGNS IS DISTRACTING."

It's not distracting if you possess the skill and experience of driving. Most drivers in my city drive according to common sense rather than traffic rules (e.g. the rule that you cannot change lanes on a crossing or 10 meters before a stoplight is commonly ignored with no major trouble).
Flasher T, who crashed his car again last week Send private email
Wednesday, December 08, 2004
 
 
I live in York, in the UK. It's a heavily-cycled city, and the council tries hard to make cyclepaths, quiet roads, etc.

One thing a cyclist friend and I are agreed upon is that cycle lanes might cause more problems than they solve. A cycle lane is often too narrow, and it seems to create a psychological division - if a driver's inside the black traffic lane, he doesn't have to watch for the cyclist in the green cycle lane. That lack of concern can be dangerous.

All that said, how does this apply to software? _Can_ the analogy be made with user interface designs?

Perhaps the best place to start discussing it is to draw a parrallel between road signs and choice dialogues - both give information and expect you to react. A signless, bare road system might be analogous to an application that used a canvas of some kind - a free space where your actions were softer and more responsive to the overall picture.

Anyway, just a starting point...
Steve Cooper Send private email
Wednesday, December 08, 2004
 
 
> Whichever country I'm in, I always drive down the middle of the road; saves an awful lot of indecision and thinking.

>> That sounds like a good strategy, but which way do you turn at roundabouts.

Having trained on the 'Magic Roundabout' in Swindon, UK

http://www.swindonweb.com/life/lifemagi0.htm

I tend to go whichever way I feel like going at the time.
Mike Send private email
Wednesday, December 08, 2004
 
 
I suppose you could say traffic signs are like the spellchecker in Word - I want to have it available for when I'm not sure what to do, but it's extremely annoying when it's always there, because I know better anyway.
Flasher T Send private email
Wednesday, December 08, 2004
 
 
This forum's ignorance it it's own ignorance is staggering. Again, I challenge any driver on this board to tell me that they've never driven to the wrong location simply because they were headed for a destination that started with the same few turns. I seriously hope nobody approaches driving as they do test taking, and that nobody believes that you learn driving or cultural differences simply by reading a book.

I don't arrive on the extreme west of the roundabout, I arrive exactly 1 carwidth away from another car going the opposite direction, and exactly one half a carwidth (on center) from the middle of the road.

I suspect Monderman's roundabout has lots of cues for you to follow that subtly guide you in the right direction, such as the aforementioned division boards, and greater-than-average visibility. None of us have seen the intersection, it could have a great deal more cues to what good driving is than we expect.

Here's another example.

You come upon a roundabout when there is little traffic and there are no parked cars. You do know which way to go - clockwise or anticlockwise, your cultural & driving memories (or your supernatural ability to instantly apply book learning to real life situations) help you make the right choice.

What prevents you from going the wrong way down a one way street? If the street you've just come off of is wider than the rest, as you make your way around the roundabout, how do you know which of the other 3 narrower roads you can take?

Perhaps you've read in a book that all odd numbered one way streets run east or south, and supergenius that you are, you can instantly apply this knowledge.

But what's to prevent mere mortals from making the wrong choice?

Of course, the answer is cues that don't rely on signs - such as paint on the floor leading in to one street or out of another, but the vast majority of people in this forum would have me believe that "it heads east and you read the handbook" is a sufficient answer.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
A great example of this kind of design in action is the (wildly popular) Sciral Consistency ( http://www.sciral.com/consistency/ ). Once you "get" how it works, you never need to be told what color means what. Other than dates and tasks, the UI is extremely bare of words, but everyone understands exactly what to do with it after spending just 2 or 3 minutes with it.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
> Haven't you ever gotten in to your car to go to one place, started driving to another by force of habit?

Err... No.

Wednesday, December 08, 2004
 
 
Sciral Consistency colours won't be borrowing your instincts from traffic lights would they?

Which would be a problem for train drivers.  Typically for train drivers, flashing lights mean stop, solid red lights mean go.  Or something like that - I've never driven a train.

And what about poor sailors?  Red is starboard, or green is, or something.  I've never really sailed either.

My point is that you are taking your 'instinctive' knowledge (subconscious yes, but learnt non-the-less?) of American Driving Mark, and trying to apply it to a roundabout in England.  And complaining that the rules of the road are different.  Well, duh?!

Obviously roundabouts, like interfaces, can be intuitive.  And most aren't.  So why do roundabouts work? Because people are cautious.

The thing that makes me be careful at roundabouts is because the people I am supposed to be giving-way to are not actually looking at me to see if I pulled out in front of them, they are looking at someone they are giving-way to.. and I am scared of being hit by an truck.

Can't see a wixard or some other user interface giving me quite that much thought.  Unless it was a big read stop button with 'do not press' written on it.. but we know what people do with those...?
i like i
Wednesday, December 08, 2004
 
 
> Haven't you ever gotten in to your car to go to one place, started driving to another by force of habit?

Yes. And I've also gotten in my car to go to one place, and driven to another simply by force of trying to follow signs (the signs weren't very good).

I don't like the Magic Roundabout in Swindon. I've been on it once, and I'm still not sure how I got off.

I take care at roundabouts because drivers in the UK (and presumably elsewhere in the world) aren't very good at driving on roundabouts. Or driving in general, and I include myself in that generalisation (most, of course, would say they're 'above average').
Kenae
Wednesday, December 08, 2004
 
 
"My point is that you are taking your 'instinctive' knowledge (subconscious yes, but learnt non-the-less?) of American Driving Mark, and trying to apply it to a roundabout in England.  And complaining that the rules of the road are different.  Well, duh?!"

No, actually I'm 'complaining' that there _are no rules on this road_.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
"Sciral Consistency colours won't be borrowing your instincts from traffic lights would they?"

Perhaps, but it would work with three neutral colors, or shades of vray as well.
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
Anyway, all the really good arguments to my premise (which is admittedly weak) are missing because everybody here just rejects it outright.

1. Even with signs you can turn the wrong way on a roundabout late at night, or any other road if your instinct is that strong and you're not paying attention. No amount of signs will prevent you from going the wrong direction if that's what's ingrained in you, though not being able to see signs (because you're looking at the back) would be a strong clue you're headed in the wrong direction.

2. The whole point of the roundabout with no signs is to focus your attention on what you're doing rather than going on mental cruise control. Hopefully even if you do go in the wrong direction, the *other drivers* and pedestrians are paying more attention and don't hit you at 120kph, or allow themselves to be hit.

Actually, I think this is a brilliant buddhist commentary on society. What could be more ironic than going around in a circle to be _more_ aware?
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
vray -> gray
www.MarkTAW.com Send private email
Wednesday, December 08, 2004
 
 
Karel Thönissen Send private email
Wednesday, December 08, 2004
 
 
Just to confuse things a little.

We have a couple of instances where we have little islands to get on to a larger island and even a virtual island which encomapasses all of them.

As you enter each island in the same way you can momentarily be facing the wrong direction.

This scares the willies out of people if they don't expect it.

There's two variant implementations I can think of, Swindon and Hemel Hemptstead.  There are hosts of other reasons for staying out of both places but this is sufficient reason enough I think.

Oh, and I just remembered we also have really tiny islands, more nipples in the road really as traffic calming measures the thing to do with these is to drive straight across them as if they didn't exist.
Simon Lucy Send private email
Wednesday, December 08, 2004
 
 
Mark,

You say "No, actually I'm 'complaining' that there _are no rules on this road_. "

However there ARE very well documented rules of road use in the UK. It's called the Highway Code (http://www.highwaycode.gov.uk ) and it is necessary for anyone taking a test in the UK to be very familiar with them - they form part of the test.

However there is no formal requirement for anyone with a non-UK driving licence to have ever even picked the book up... a bit of an oversight!

Roundabouts have a set of rules that you learn when learning to drive. I would expect to see signs on how to use them as much as I would expect a sign in my car tellimg me how to change gear.

Signs are only needed when there is an exception to standard behaviour - You have no way of knowing a road is one-way unless it is signed. You don't need a "2-way" sign on every other road.
Ant
Thursday, December 09, 2004
 
 
most roundabouts (in the UK) do have 'go left' arrows on them, and the final twist of the lane markers makes you face slightly left.

And if you arrive from aboard at a major UK airport, or a major port, you can expect to see 'drive on left' warning signs on the exit roads as you approach the real roads.

If you can read English, that is..

(Is there some obscure Pacific island where the culture has no concept of arrow signs?)
i like i
Thursday, December 09, 2004
 
 
I'm living in Ontario, Canada, where roundabouts are virtually unknown. Most people have heard of them, as 'those traffic circle things you British have', but not seen one. There is nothing about them in the Ontario driving manual. However in the last few months my city decided that it wanted to install one. Certainly it was the first in the region; possibly in the whole of Ontario.

As a Brit, brought up on roundabouts since childhood, the region's approach to this introduction has been interesting. Stories were placed in newspapers about how this new junction type was going to be introduced, including an explanation of why roundabouts were being used. Months in advance, every house in the region was sent a leaflet, explaining why roundabouts were being introduced, what their history was, which countries successfully used them, and how to approach them as driver, cyclist and pedestrian. The sequence was described in exact detail

The roundabout was opened a couple of months ago, and I drove off to visit it, hoping for a little nostalgic driving round in circles. Well, you could hardly see for warning traffic signs. First there is an entirely new kind of roadsign; a little 'yield' (give way) sign with a roundabout in the middle. Then the directional signs. Then a big permenant sign saying 'yield to traffic in roundabout'. Finally there are a couple of temporary signs, with letters a foot high, saying 'yield', 'yield to traffic in roundabout', and probably (though this became a blur) 'really make sure you yield'. None of this 'let people work it out for themselves' approach for us Canadians.

Actually I think roundabouts are really going to help North American trafic flow. The standard low-cost junction (for those of you who haven't driven here) is the four way stop; approaching it you have to stop, check for traffic, and then move off in the order you arrived. And yes the stop is enforced; cruising through the junction, even with nothing coming, will get you a ticket if there happens to be a lurking cruiser. The big advantage of the roundabout is that you can go through it at a reasonable speed, provided there is no traffic and the visibility is OK. That alone might make a noticeable difference to North American fuel comsumption.
David Clayworth
Thursday, December 09, 2004
 
 
> (Is there some obscure Pacific island where the culture has no concept of arrow signs?)

On some islands those signs mean "beware, the natives are distinctly unfriendly".

Friday, December 10, 2004
 
 
The point I was trying to make by highlighting this WIRED  article is that sometimes seemingly good clear interface design (like lanes and traffic signs and road markings) does not achieve your objectives.

While not as apparant with single user applications applications, social software is proving a good example of this.  This bulletin board not automatically quoting of replies is one instance. Sometimes features or ease of doing things impede the real purpose of the tool. 

Sometimes making things slightly harder to do forces people to be more aware and thus makes contributions more valuable /or attracts the kind of people you want.

Simon
Simon Tzu Send private email
Friday, December 10, 2004
 
 
It seems this thread is being continued here

http://discuss.joelonsoftware.com/default.asp?design.4.41832.9

Hopefully a fresh batch of people can tell me that everyone follows the law to the letter every moment of every day.
www.MarkTAW.com Send private email
Saturday, December 11, 2004
 
 
My favorite aside about traffic circles: In Washington, DC there are tons of them, as there are diagonal streets (named after the states in the US) that cut across the otherwise (fairly) regular grid of the city's streets. Almost all of these traffic circles have traffic lights at every intersection, causing horrendous traffic patterns. To make what would be a left turn in a DC traffic circle it is sometimes necessary to stop for four or five red lights.

Brings being "unclear on the concept" to new heights, if you ask me.

Jeremy
JeremyNYC Send private email
Monday, December 13, 2004
 
 

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