Re: Re: Small Monumental Buildings . . .

The Architects, and architectural enthuasiasts in the audience are just going to hate this rotten turn the discussion has taken, but heck,… I like computers, I like calculations that involve discovering the behaviour of large numbers of agents, and firmly believe that someday, all of this sort of research is going to amount to something useful to the urbanist/architect. I just couldn’t resist, posting this piece,…

Yeah, the Suroweicki book is grand,… I must check out that Crowds and Power Book too, after I finish the Wisdom of Crowds,.. I must scribble down all the others like it I have picked up over the last year,… Suroweicki suggests a certain book/study done on New York city pedestrians, called ‘City’, by William H. Whyte. I think the study of pedestrians, an understanding of how traffic engineers always want to design the city, from their perspective,… I think that is all going to be useful in solving problems that Dublin city and other Irish towns and villages, will face in the coming decades. So this whole ‘bottom-up’ idea about organisation is important – whether it be stock markets, ant colonies or pedestrians.

Trouble is though, most Architects have no clue what a pedestrian is, the notion is not a part of their toolkit,… they tend to stress more, things like ‘drawing’,.. and that kind of design. So it is too easy to ‘blame’ traffic engineers for pushing mechanised movement, when Architects themselves didn’t do any homework about pedestrians either – except this is improving, several architects I have listened to speaking/presenting lately in Ireland, seem to be getting there, painfully perhaps, but at least, getting there. I still think a more determined effort is required from first year in Architectural Schools though. But believe me, I have sat in lectures where a tutor attempted hopelessly to ‘animate’ this kind of subject matter – sometimes, with sucess, sometimes without – but in general the whole undertaking proved to be a terrible load of stodge,… I dunno, perhaps Architects aren’t designed to grasp these sorts of notions, or to present them with any enthuasiasm?

Any views?

Am I way off base?

Brian O’ Hanlon.

In the early 1990s, the economist Brian Arthur tried to figure out whether there really was a satisfying solution to this problem. He called the problem the ‘El Farol problem’, after a local bar in Santa Fe that sometimes got too crowded on nights when it featured Irish Music. Arthur set up the problem this way: If El Farol is less than 60 percent full on any night, everyone there will have fun. If it’s more than 60 percent full, no one will have fun. Therefore, people will go only if they think the bar will be less than 60 percent full; otherwise, they stay home.

How does each person decide what to do on any given Friday? Arthur’s suggestion was that since there was no obvious answer, no solution you could deduce mathematically, different people would rely on different strategies. Some would just assume that the same number of people would show up at El Farol this Friday as showed up last Friday. Some would look at how many people showed up the last time they’d actually been in the bar. (Arthur assumed that even if you didn’t go yourself, you could find out how many people had been in the bar.) Some would use an average of the last few weeks. And some would assume that this week’s attendance would be the opposite of last week’s (if it was empty last week, it’ll be full this week).

What Arthur did next was run a series of computer experiments designed to simulate attendance at El Farol over the period of one hundred weeks. (Essentially, he created a group of computer agents, equipped them with the different strategies, and let them go to work.) Because the agents followed different strategies, Arthur found, the number who ended up at the bar fluctuated sharply from week to week. The fluctuations weren’t regular, but were random, so that there was no obvious pattern. Sometimes the bar was more than 60 percent full three or four weeks in a row, while other times it was less than 60 percent full four out of five weeks. As a result, there was no one strategy that a person could follow and be sure of making the right decision. Instead, strategies worked for a while and then had to be tossed away.

The fluctuations in attendance meant that on some Friday nights El Farol was too crowded for anyone to have fun, while on other Fridays people stayed home who, had they gone to the bar, would have had a good time. What was remarkable about the experiment, though, was this: during those one hundred weeks, the bar was – on average – exactly 60 percent full, which is precisely what the group as a whole wanted to be. (When the bar is 60 percent full, the maximum number of people possible are having a good time, and no one is having a bad time.) In other words, even in a case where people’s individual strategies depend on each other’s behaviour, the group’s collective judgement can be good.

A few years after Arthur first formulated the El Farol problem, engineers Ann M. Bell and William A. Sethares took a different approach to solving it. Arthur had assumed that the would-be bargoers would adopt diverse strategies in trying to anticipate the crowd’s behaviour. Bell and Sethare’s bargoers, though, all followed the same strategy: If their recent experiences at the bar had been good, they went. If their recent experiences had been bad, they didn’t.

Bell and Sathare’s bargoers were therefore much less sophisticated than Arthur’s. They didn’t worry much about what the other bargoers might be thinking, and they did not know – as nights when they didn’t show up. All they really knew was whether they’d recently enjoyed themselves at El Farol or not. If they’d had a good time, they wanted to go back. If they’d had a bad time, they didn’t. You might say, in fact, that they weren’t worrying about coordinating their behaviour with the other bargoers at all. They were just relying on their feelings about El Farol.

Unsophisticated or not, this group of bargoers produced a different solution to the problem than Arthur’s bargoers did. After a certain amount of time had passed – giving each bargoer the experience he needed to decide whether to go back to El Farol – the group’s weekly attendance settled in at just below 60 percent of the bar’s capacity, just a little bit worse than that ideal central planner would have done. In looking only to their own experience, and no worrying about what everyone else was going to do, the bargoers came up with a collectively intelligent answer, which suggests that even when it comes to coordination problems, independent thinking may be valuable.