Living in Hong Kong I can’t help but be fascinated by the way pedestrians self-organize. It’s one of the densest populations on earth, so navigating one’s way through the urban jungle requires a lot of mental processing. The pedestrian bridge in Wanchai that goes from the subway to my office is probably half a kilometer, ten meters wide and nearly always chocabloc with people going both ways. There are no signs indicating which side people should walk on, and it seems to vary from one day to the next, but somehow people organise themselves so one side goes one way, one the other. I guess ants and all other life-forms do it, but it’s still impressive to watch.
That’s not to say it’s perfect. Folk handing out leaflets and stuff — quite aggressively, thrusting them into your hand; not quite how I remember it — disrupts the flow as the ants, sorry people, weave their way around them. Then there is the occasional textcident, or someone wanting to move faster than the group. (That’s usually me, carrying a steaming hot cup of joe.) I’ve always wanted to get five or so people together and see how much it takes to move the flow of traffic from one side to another. Is there any data on this kind of thing?
In the subway there’s a different problem. On the whole Hong Kong people are quite good at allowing passengers off before they get on, but there’s a subtle disincentive to do the proper lining up built into the platform guidelines, illustrating the problem of groups cooperating.
Passengers boarding are supposed to queue up in the orange lines behind the white arrows, allowing alighting passengers to follow the green arrow between the waiting lines. But of course it’s not in one line’s interest to wait because that will push the alighting passengers towards the space they have left vacant and leave the other side of the open door free for the other boarding line. Indeed, this tends to happen all the time: One side inches forwards first, pushing open a breach in the crowd of alighting passengers, who crowd out the other line, so that by the time they board all the seats have been occupied. So you have competing lines of waiting passengers, all knowing the game. Doesn’t make sense to me.
Singapore, if I’m correct, has a way of doing this, though I can’t remember how. My guess is a better way of doing all this would be to have some doors for getting on, some for getting off, or else have all boarding passengers line up on one side of the door. That, or you could position snipers inside the tunnels who occasionally take out those people who don’t wait for everyone to alight before boarding. That might work too.