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> If you want to change lanes, you need to cut someone off. It's just expected. If you don't drive like that, it's almost as if the other drivers don't understand your intention, and you get nowhere.

This is going to be a major challenge or at least a major change for Waymo. It's been a while since I've driven near one, but they were very timid with lane changes. Also, there was that published incident when the Waymo car tried to change lanes into a bus.

There's unwritten rules about who you can cut off. My experience is from LA freeways, the rules may be different in NYC, but the concept is the same. Buses and other vehicles, usually no, but sometimes. Marked taxis, no. Older vehicle with lots of scrapes, probably no. Also, the proper time to signal your lane change is often after your car is already in the lane enough that you can't be displaced.

Why would you not cut off buses and taxis?

They are professional drivers, so you can rely on them being better than the average drivers in difficult situations like having to brake suddenly, so I think you should cut them off preferentially.

At least where I drive, taxis drive very aggressively and will win at chicken with me everytime. Sometimes professional means in tune with the equipment and willing to drive at the edge of its capability.

Busses are big and may not stop quickly. If traffic is tight enough that I need to force my way into an opening, traffic may stop suddenly and I don't want to find out if the bus can stop behind me, because if not, I need to shop for a new car and new pants. If things are moving very slowly, then yeah, you can cut them off.

At least in San Francisco a bus is king of the road. They will run a red light at normal speed and just beep beep to tell everyone that this is happening. An abrupt stop isn't possible because people are standing inside and might get hurt.

Same reason why a bus will not suddenly slow down to let you into their lane unless lives are at stake. Which at sub 30mph speeds they're not.

Best to treat a city bus like it's a train.

You can think of being a bus driver in city traffic as a constant trolley problem. As a professional driver, do you risk injuring 50 people inside the bus or 1 idiot on the road?

Buses take much longer to slow down than cars and the driver also likely can't see you if you cut them off with little room to spare. So besides not wanting to be a jerk there's self-preservation to think about.

Do not mess around with big city bus drivers, either on the bus or on the road. They are some of the toughest people in the city. Think of what they deal every day.

> I'd honestly be excited if they pulled it off. A robot driving like a real New Yorker, but presumably a lot safer? How cool would that be!

Part of the attraction of self-driving cars is that they will be safer. But as examples like these show, a significant part of danger in driving is completely intentional, especially in cities. You need to deliberately risk crashes all the time to get anywhere and to discourage others (such as pedestrians) from getting in the way. A lot of driving involves such violent threats. I don't know what fraction of crashes comes from this sort of thing, but it would be interesting to estimate, and it would provide an upper bound on the safety advantage of autonomous cars in cities.

Also it's interesting that a robot is more capable of doing dangerous aggressive type of driving if you factor in how many sensor and calculation power it have over a human

Check out this video they posted recently of them driving in SF, which isn't much worse than NYC.

https://www.youtube.com/watch?v=2CVInKMz9cA

Look how it handles the bike going against traffic or how well it sees the pedestrians from far away. It's also quite a bit more assertive I find than in Phoenix.

If it's gonna full stop like that in NYc, gonna backup traffic...

You can slow down but you generally don't stop for pedestrians j walking or bikes going wrong way.

Pedestrians generally know when to speedup/slowdown to cut through moving traffic (not always the case of course there are accidents).

If the person halts in way of traffic than sure do a full stop.

> having driven around NYC for many years now, I can say that it's basically necessary to be an extremely aggressive driver here. If you want to change lanes, you need to cut someone off. It's just expected. If you don't drive like that, it's almost as if the other drivers don't understand your intention, and you get nowhere.

It's beyond that: by behaving in an unexpected manner, and by disrupting the flow of traffic, you are a danger.