A Low Cost Approach to Improving Pedestrian Safety with Deep Learning

And if we had less cars, buses would be less of all of those things.

This is a problem that can be addressed by dedicated bus lanes. But if you're going to have dedicated lanes, then it may make sense to go all of the way to light rail. Also dedicated lanes get push-back from unhappy car commuters. Who tend to have an outsized influence.

Many cities worldwide have had luck combining dedicated bus lanes, with "park and ride" lots, and congestion parking in downtown. Now you're providing both carrots and sticks to push people towards a hybrid trip that starts with a car, and then switches to bus in the high density areas. But it is a combination that tends to be politically unpopular in the USA.

More frequent buses tends to have a split effect. The first-order effect is linearly fewer passengers per bus. The second-order effect of people now switching to buses has to be quite strong (and often is) to overcome this direct effect.

I happened to travel from Amsterdam to Boston today (missing King’s Day). There was no chance I wouldn’t take the train to the airport on the Amsterdam end. There was equally no chance that I would take mass transit on the Boston end, despite living in Cambridge.

I haven't looked at the research recently, but my understanding is that while more frequent service is strongly correlated with higher average passenger counts, the causation seems to be that higher average passenger counts justify increased bus service, and not that increased bus service generally results in higher passenger counts.

Better route coverage likewise.

Reduced prices are complicated. That does increase usage, until the prices drop so far that you attract homeless people who your would-be passengers are scared of. It turns out that making mass transit passengers feel safe is a very important consideration.

First of all BOTH buses and cars last an average of 12 years. As a society, replacing one fleet takes similar time to replacing the other.

Second, electric vehicles are currently 7.2% of all new cars sold in the USA, and only 2% of new buses sold in the USA. See https://www.coxautoinc.com/market-insights/q1-2023-ev-sales/ and https://www.iea.org/reports/global-ev-outlook-2023/trends-in... for verification. So while there is great fanfare and publicity around cities switching, by and large they haven't chosen to yet.

Why the discrepancy? There are a lot of reasons, but I wouldn't discount the fact that buses spend a larger fraction of their lives actually being driven, and so the fact that fueling is faster than recharging matters more for buses than cars.

Therefore even though it costs more to replace all of the cars in America, economics suggest that this will happen before the buses all convert over.

In other countries such as Japan public transit is generally faster then private transportation. I think one of the reasons you see a low adoption of public transportation in some North American cities is because it can do the opposite and extend your trip duration by a significant amount. Safety is obviously another factor. It seems like in a lot of places pedestrians are treated with disregard. Pedestrians being able to safely commute within their communities shouldn't be controversial, but for some reason it is.

Pause.

You're the one who dismissed gathering evidence about real usage of streets because the only sensible solution is to live in dense housing and use mass transit. Which fails to recognize that solving the density problem involves major political battles that make it a generally nonviable solution to real problems that cities are faced with. Refusing to consider a politically workable solution because it is not your preferred one is counter-productive. And your preferred solution is NOT politically workable.

Second, in my reply to a sibling comment I showed evidence that electrification of cars is proceeding faster than electrification of bus fleets. So even though there are more of them, electrifying cars is actually proving to be politically easier.

Third, I picked on buses because they are the easiest form of mass transit to move to from cars. If buses can't be made to work for a particular metro area, then nothing else is likely to work either. And buses are failing to work very well in most places where they are used.

And fourth, the big problem with buses in America is population density. We're driving mostly empty buses that make little environmental sense. This is a sign that we're not actually underinvesting in bus routes. But it is hard to make mass transit work when people aren't all in one place. And as much as you might wish it otherwise, we're not inclined to congregate in a small area for convenience.

It is unfortunately more complicated than that.

First, the density of a city is different than the density of the area over which people live who commute to that city. Even American cities with comparable density are not necessarily as dense on that apples to apples comparison.

Second, you have to look at commute distance. The average American commutes around 40 miles each way. The average European commutes around 9 miles each way. 4x the distance = 16x the area, which means that adding a bus from A to B is likely to be helpful for about 1/16 the people. And that, right there, is going to explain a HUGE difference in ridership on mass transit.

Are you thinking just of roundabouts that include a raised middle and/or central reservations on approaching roads? In general, roundabouts need no more space and cost than a regular road would, see e.g. https://goo.gl/maps/Y6jzLq5SuYzMMf2a6

GP was most likely thinking not of large roundabouts that take the place of major intersections, but the smaller traffic-calming type where the center can be as minimal as a 3 foot wide concrete block. They can be fit into pretty much any intersection because their purpose is not to change the path so much as to, frankly, eat up whatever extra space is available, which forces cars to slow around them.

There's a mini roundabout in my neighbourhood. It is about the same size as the intersection it replaced.

They just leave the middle flat so vehicles that don't fit (and people who can't be bothered to go around) can drive on it.

First of all if you are going to say that my remark is "analogous" to a lie, and that I "intentionally" mislead people in the course of bicycle infrastructure advocacy, then my reply is that you are analogous to a guy who needs to intentionally fuck off. Where the hell do you get off saying something like that about me?

Secondly, there is a massive latent demand for cycling infrastructure in highly populated places that are suitable for cycling. That there are other places unsuitable for cycling is irrelevant. Another thing we often say on this topic is there are no transportation solutions to land use problems. But in America even when the development pattern is reasonable the infrastructure for cycling still doesn't exist. The dangerous, unpleasant, and inconvenient scattered bike lanes that we have in most American cities are acceptable to < 1% of potential cyclists, which is why the bicycle mode share in most American cities is << 1%.

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Nobody wants to convince the majority of anything. Most cities would be happy to raise the share of bikes by a few percentage points.