Comment by VLM | Hacker News Reader

Comment by VLM | Hacker News Reader

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"a massive impact in terms of social equalization."

The folks who don't like that, can prevent the equalization by careful scheduling and have already done so. I live in a nice civilized town/city and the bus routes travel within one block of every square inch of the city hourly. So average transit time is one hour, max theoretical (assuming not missing the bus, etc) is a bit less than three hours. Unfortunately I can drive in my car between any two points in 10 to maybe 15 minutes worst case.

I can, and have, repeatedly out walked the city bus by walking direct pt-pt rather than meandering all over the city. Its really more of a bad weather service, or a service for people who can't walk.

Also I live in a civilized town/city but work in the neighboring uncivilized dump of a city, which has slightly better bus service, but schedules have been "optimized" to keep us separate such that my commute via bus would seem to only take about two hours each way, but careful optimization of schedules increases that to at least three hours with lots of standing around at the transfer point. Of course in a car its about 20 minutes, maybe 40 at rush hour.

And that's how you keep social groups separated even with low subsidized (or even free!) bus fares.

It sounds like your city would be a great candidate for decent bike lanes.

That sounds quaintly conspiratorial, however it is incredibly complex to optimize bus routings, especially given financial limits most systems operate under. Any change will always be at the detriment of someone else, and the last mile(s) problem is enormous.

Logistics is hard in general, is my impression. In fact, most of the interesting problems logistics seem to reduce to NP-complete problems, which has some unfortunate consequences for finding optimal solutions.

The generalized form of most logistics problems reduce to NP-complete, but we are also almost always working in a system with much more structure than the general problem, so a polynomial time solution may be available. Also, many NP-complete problems can find 'near' optimal solutions in polynomial time.

For example, consider the traveling salesman problem in a metric space. We can construct a minimum spanning tree in polynomial time, and we know that traversing this tree takes no more than twice as long as traversing an optimal solution to the traveling salesman problem. By using the triangle inequality, we can further optimize our solution, still in polynomial time.

There is also a bit of a self-reinforcing system in play. Good access to mass transit makes an area more desirable and more expensive, so rich people end up living there. Bad access to mass transit makes an area less desirable and less expensive, so poor people end up living there. But then there is less incentive to expand service into those areas, because it's just a bunch of poor people...

Sounds like London. I live in London and these days I just cycle everywhere, but I´m sure that walking wouldn't be much slower than the bus.

London, UK? Which happens to have one of the best and largest underground system in the world covering almost all areas of the inner city. Then you have the train service to get you out to the outer parts, and then the buses?

Admittedly, once you get to rural parts of the UK the public transport sucks, but day or night, I can get myself around London without too much of a wait.

Even just purely by bus, London is night and day different from any American city. You rarely have to wait more than 10 minutes for a bus, and often they come just a few minutes apart.

Now, like the GP, I also cycle around London, and it is by far the best way to get through central London during rush hour, but bus drivers here are aggressive and they tend to be quite a bit more efficient than their sparsely populated American counter-parts who are brow-beaten into submission by aggressive American sedan drivers who've never heard of public transportation or sharing the road.

Some routes are very sub-optimal though. But you can't satisfy everyone's needs.

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