Stuck in a Dead End

I tried to start my bike season today and ended up with a flat tire. It was my own fault.  After many years of riding my bike, I still cannot properly change a tire. I “fixed” my bike yesterday and I think I just got the inner tube caught on the rim. It just needed a little pressure to blow out. I wasn’t too far from home, so I could walk back in around a half hour. It was not a complete loss. The walk was really nice and I had a chance to think about a few things.

What I thought about was Nash equilibrium. I can’t say I am an expert on the details, but as I understand the simple version, Nash proved mathematically what we perceive intuitively but imperfectly. It is possible to have stability at a situation that is bad and everyone agrees is bad.  However, each person makes perfectly logical choices that lead to this outcome.    

The way that it works is that if almost everybody makes the “good” choice (call it choice A), they are all better off.   But if not enough people make that choice (they choose choice B), those that choose A suffer more than those who make the bad choice (B).  So everybody tries to figure out what the majority will do, while complaining about the stupidity of the herd. These sorts of equilibria have tipping points.  If enough people come to think others will choose outcome A, they all will pile on. The same goes for the other option.

Nash, BTW, is the guy played by Russell Crowe in the movie “A Beautiful Mind.” The real Nash won the Noble Prize for his work in mathematical economics. If you study game theory, you have to study Nash.

The example of a Nash equilibrium I thought about on my morning walk was traffic and blocked roads.  Northern Virginia has horrible traffic problems. Many of them result from the stupid way streets are laid out.  Unlike a logical grid layout you find in many cities, Northern Virginia’s road system looks more like a river drainage basin, with dead end tributaries flowing into larger and larger streets. There might be only one – usually winding – road that you can use to get where you want to go. Parallel streets, if they exist at all, are blocked or dead ended.

I think that the original road system was based on cow paths and Indian trails. We have Braddock Road, which is the course that General Braddock took to Pennsylvania during the French and Indian wars. Since he insisted on building a road, the French and Indians saw him coming and wiped him out.  George Washington saved some of the troops and it was the start of his good reputation.

Onto the cow path system was appended a system of cul-de-sacs and dead end streets.  This is where the Nash equilibrium starts to play. People prefer to live on quiet streets and the best way to ensure a quiet street it to make sure that it doesn’t go anywhere. So builders and planners create neighborhoods with no-through streets. This means that you might have to drive ten miles to travel one mile if you could go straight. It also throws all the traffic onto a few overcrowded roads.  

I walked home along Sandburg Street. It parallels Gallows Road, which is gridlocked at the time I was walking.But there were no cars on Sandburg. That is because you cannot get there from here in a car.  Sandburg has a dead end right in the middle. This is what you see on the picture. The wide and well paved road comes to an end in a patch of grass around five yards wide. It has been this way a long time, because some trees have grown in. Then it starts again. I am sure this was originally a real dead end.  Now they cannot make it grow through because the local residents will complain. There are lots of place like this in Northern Virginia.  Everybody agrees that we would all be better off if we could spread the traffic and drive the shorter distances. But nobody wants to give up his own quiet street.

BTW – Did you hear the story about the guy asking for directions? He asked an old man, “Does this road go to Chicago?” They old man replied, “No. I have lived here all my life and I have never seen it go anywhere.”

So the State keeps on widening the roads. The irony is that they widen the empty roads too.  As you can see in the picture, Sandburg is a fairly wide road, considering it doesn’t really go anyplace.  At least this road has a place where pedestrians and bikes can get through. Most don’t even do that because everybody wants privacy.

There is no way out of this equilibrium. You might say that we have reached a dead end.