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Using Countdown Clock Data to Understand the New York City Subway

toddwschneider.com

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Re: Using Countdown Clock Data to Understand the New York City Subway

#31

Post by rayiner »

Alex3917 wrote: post #27
rayiner wrote: post #21

Earlier quoted context omitted.

It's not a question of whether "one of the richest cities on the planet" can "fund serious upgrades." It's how much money are New Yorkers willing to throw into a system where it takes several times as much money to do the same thing as other countries? https://www.nytimes.com/2017/12/28/nyregion/new-york-subway-... . New York is rich, but so is London. Based on that wealth, there is a certain amount of money New York…

> Our public services suck, which means that they turn into safety nets instead of something that are broadly used by the population. If roads, trains, schools, water, electricity, libraries, etc. don't count as widely used, what exactly does?

Rich people buy bottled water (and our water system is a disaster that’s poisoning poor kids with lead). Rich people either send their kids to private schools, or carve out enclaves with public schools that have just other rich people (while the “safety net” inner city schools deteriorate). Electricity isn’t a “public service.” For the most part, private companies provide electric service in the US using private infrastructure. Nobody uses libraries.

That leaves our roads, which are much crappier than in say Germany or Japan.

Re: Using Countdown Clock Data to Understand the New York City Subway

#32

Post by tialaramex »

onion2k wrote: post #11
RossM wrote: post #6

Earlier quoted context omitted.

I feel it's worth reminding that there's a difference between autonomous trains, driverless trains and unattended trains. The L train is considered Grade of Automation 2 - it starts and stops itself, though it has someone in the driver's seat who controls the doors and gives control to the ATO system. Driverless (GoA3) trains move that role to a train attendant who controls the doors from within the train. Unattended…

Does the DLR count as a GoA3 train? There isn't a driver sitting at the front.

Yes, each DLR train has a Passenger Service Agent, who is fully trained in the safe driving of a DLR train by a human, but during normal operation they're walking around in the train, closing the doors when it's ready to leave, and so on.

The PSA will drive the first train on each route every morning, since unlike the train's automation their human eyesight allows them to detect some very dramatic mistakes, for example if maintenance engineers left a metal trolley full of equipment halfway across the line, the train can't see that but the PSA can hit the "Stop" override. Normally they don't drive, allowing passengers to sit at the very front of the train, like on a roller-coaster, the manual controls are under a lockable panel.

The train also has a "full" manual mode in which the PSA is able to explicitly drive it wherever they want, rather than just stopping unexpectedly if they see a problem, but in this mode the train deliberately cannot reach its normal speed, because humans have poor reactions and so it would be too dangerous without the machine supervising.

Re: Using Countdown Clock Data to Understand the New York City Subway

#33

Post by crdoconnor »

rayiner wrote: post #30
crdoconnor wrote: post #23

Earlier quoted context omitted.

>Costs are the fundamental problem with the MTA (and D.C.'s WMATA), and those are union problems, not management problems. Managerial corruption causing cost overruns like this does not even tangentially involve unions: "The New York City subway system has continued to deteriorate, rankled by massive delays, misspent funds, and widespread claims of corruption. On Friday, the feds confirmed the corruption part by secu…

What is the acale of that in comparison to paying more worksrs than you need more money than you need to? Most of MTA’s expenses are labor costs. Contracting corruption is bad and illegal, but is not what’s driving the costs.

That's certainly MTA management's narrative when asked by, say, the New York Times.

Re: Using Countdown Clock Data to Understand the New York City Subway

#34

Post by tomjakubowski »

rayiner wrote: post #31
Alex3917 wrote: post #27

Earlier quoted context omitted.

> Our public services suck, which means that they turn into safety nets instead of something that are broadly used by the population. If roads, trains, schools, water, electricity, libraries, etc. don't count as widely used, what exactly does?

Rich people buy bottled water (and our water system is a disaster that’s poisoning poor kids with lead). Rich people either send their kids to private schools, or carve out enclaves with public schools that have just other rich people (while the “safety net” inner city schools deteriorate). Electricity isn’t a “public service.” For the most part, private companies provide electric service in the US using private infr…

Total attendance, NYPL system in FY2016: 13,867,000 (2M library card holders, 729,000 active)

Total attendance, New York Mets in MLB 2016: 2,460,000

Total attendance, New York Giants in NFL 2016: 630,312

"Nobody" uses libraries, indeed. http://council.nyc.gov/budget/wp-content/uploads/sites/54/20...

Re: Using Countdown Clock Data to Understand the New York City Subway

#35

Post by jwr »

RossM wrote: post #6
anthonybsd wrote: post #2

>The L train is also the only line that uses modern >communications-based train control (CBTC), which allows >trains to operate in a more automated fashion. It's not "more automated fashion", it's fully automated, LIDAR and all - they are fully autonomous. L trains have operators because of unions throwing a fit and most of the times they sit there twiddling their thumbs.

I feel it's worth reminding that there's a difference between autonomous trains, driverless trains and unattended trains. The L train is considered Grade of Automation 2 - it starts and stops itself, though it has someone in the driver's seat who controls the doors and gives control to the ATO system. Driverless (GoA3) trains move that role to a train attendant who controls the doors from within the train. Unattended…

> I don't think we'll see a GoA 4 tube for many years

Perhaps I'm missing something, but I used to ride a fully automatic (e.g. there was no driver, not even a cabin for one) subway line in Lyon back in 1994/1995.

Re: Using Countdown Clock Data to Understand the New York City Subway

#36

Post by tialaramex »

exegete wrote: post #10

The author does briefly mention this, but the countdown clocks are not every accurate. I often see a wait time of "3 min" and then it's there in the next 10 seconds. Or you can see the opposite where it just hangs on "3 min" for a minute or two and was really 5 minutes away. In reality it should just report at its accuracy, e.g., " PS, why do people stick their necks over the tracks to look if a train is coming?

Accurate countdown clocks are hard, they by definition involve predicting the future which is widely accepted to be a Hard Problem :)

More specifically there are two major problems one of which is expensive to solve, and the other is impossible to solve.

The expensive one is providing and making use of lots of sensors so that we can have the best possible evidence on which to base our prediction. Most obviously we need to sense where the train is - the more accurately the better. But it's also valuable to know if the train is moving, and even if the previous platform is full of passengers who will board it before it can leave, or empty.

The estimates may prove wrong because of something as dramatic as a fault, or as trivial as somebody's coat trapped in the door.

London's system has always seemed fine to me, but it's noticeable that buses (for which London also provides countdown clocks) have much poorer accuracy, because as well as the vagaries of passengers they must contend with variable traffic. It only takes one idiot trying to reverse a lorry onto a major street to add 3-4 minutes delay to your bus and of course if you can't see the lorry you have no idea that's where the time went.

I don't agree that it makes sense to reduce the displayed precision as you suggest. The problem isn't with precision, it's accuracy, and you can't really fix that by reducing precision.

Re: Using Countdown Clock Data to Understand the New York City Subway

#37

Post by gowld »

anthonybsd wrote: post #2

>The L train is also the only line that uses modern >communications-based train control (CBTC), which allows >trains to operate in a more automated fashion. It's not "more automated fashion", it's fully automated, LIDAR and all - they are fully autonomous. L trains have operators because of unions throwing a fit and most of the times they sit there twiddling their thumbs.

> most of the times they sit there twiddling their thumbs.

Most of the times?

What would happen if operators were twiddling their thumbs (or absent) the rest of the times?

Uber's self-driving car also has an operator "twiddling their thumbs most of the times", but I wouldn't want to eliminate the operator.

Re: Using Countdown Clock Data to Understand the New York City Subway

#38

Post by gowld »

exegete wrote: post #10

The author does briefly mention this, but the countdown clocks are not every accurate. I often see a wait time of "3 min" and then it's there in the next 10 seconds. Or you can see the opposite where it just hangs on "3 min" for a minute or two and was really 5 minutes away. In reality it should just report at its accuracy, e.g., " PS, why do people stick their necks over the tracks to look if a train is coming?

Same reason people reload their social media feeds and forum websites. They crave new information.

Re: Using Countdown Clock Data to Understand the New York City Subway

#39

Post by chimeracoder »

gowld wrote: post #37
anthonybsd wrote: post #2

>The L train is also the only line that uses modern >communications-based train control (CBTC), which allows >trains to operate in a more automated fashion. It's not "more automated fashion", it's fully automated, LIDAR and all - they are fully autonomous. L trains have operators because of unions throwing a fit and most of the times they sit there twiddling their thumbs.

> most of the times they sit there twiddling their thumbs. Most of the times? What would happen if operators were twiddling their thumbs (or absent) the rest of the times? Uber's self-driving car also has an operator "twiddling their thumbs most of the times", but I wouldn't want to eliminate the operator.

> Most of the times?

Well, they're not always twiddling their thumbs. Every time the train comes in to the station, they have to open the window and point up at the zebra-striped sign.

That's not literally twiddling your thumbs, but I'll leave it as an exercise to the reader to determine whether that serves any purpose on a fully-automated train that couldn't be eliminated with no loss of functionality, safety, or convenience.

Re: Using Countdown Clock Data to Understand the New York City Subway

#40

Post by tptacek »

rayiner wrote: post #31
Alex3917 wrote: post #27

Earlier quoted context omitted.

> Our public services suck, which means that they turn into safety nets instead of something that are broadly used by the population. If roads, trains, schools, water, electricity, libraries, etc. don't count as widely used, what exactly does?

Rich people buy bottled water (and our water system is a disaster that’s poisoning poor kids with lead). Rich people either send their kids to private schools, or carve out enclaves with public schools that have just other rich people (while the “safety net” inner city schools deteriorate). Electricity isn’t a “public service.” For the most part, private companies provide electric service in the US using private infr…

Our roads are not much crappier than Germany's roads --- or, at least, not much crappier than the roads in Bavaria.
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