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Analyzing Caltrain Delays

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Re: Analyzing Caltrain Delays

#11
post #5

Earlier quoted context omitted.

I can't help but feel that if there was a BART line where the Caltrain currently runs, things would be about a hundred times better than they currently are, on all fronts. Alas...

Electrified Caltrain is infinitely preferable to BART.

Only if you get rid of the behemoth slowpoke trains, elevate the rails, add more rail lines, and add a corridor to the East Bay. The Millbrae Caltrain/BART connection is a joke.

Re: Analyzing Caltrain Delays

#12
post #5

Earlier quoted context omitted.

To be (grudgingly) fair to Caltrain, a lot of things are perhaps indirectly out of their control-stuff like suicides (until you get gated platforms to stop people from jumping in front of Baby Bullets) and vehicles stopped on tracks are hard to predict. Likewise they are a victim of their own success-standing room only trains make boarding and unboarding longer than they have to be. Of course, Caltrain has put off el…

I can't help but feel that if there was a BART line where the Caltrain currently runs, things would be about a hundred times better than they currently are, on all fronts. Alas...

What I perceive as the good bits of BART could be replicated on Caltrain with much less effort than replacing Caltrain with BART: the off-peak timetable. Caltrain does better for longer trips in my (limited to South Bay) experience, which makes sense since Caltrain average trip length is 1.5x to 2x longer than BART's. But overall, getting improvements seems much less technical and more political, and neither system seems to have much luck.

Re: Analyzing Caltrain Delays

#13
post #5

Earlier quoted context omitted.

I can't help but feel that if there was a BART line where the Caltrain currently runs, things would be about a hundred times better than they currently are, on all fronts. Alas...

BART should've taken over SP's Peninsula Commute in the 70s, when SP really wanted to get rid of it. Even better would be if BART ran standard gauge and overhead wire.

BART tried to, but IIRC San Mateo county unwisely pulled out of the project back in the early days. Part of the reason that it took ages to get BART to Millbrae. That Daly City - Colma - SFO extension took way longer than it should have.

Re: Analyzing Caltrain Delays

#14

Earlier quoted context omitted.

Electrified Caltrain is infinitely preferable to BART.

Why electrified vs normal caltrain? Will that decrease the variance or door to door time of using caltrain?

There is a lot of info here [1], summarized here [2]. Probably of the most interest to most people is "Improved Train Performance, Increased Ridership Capacity and Increased Service: Electrified trains can accelerate and decelerate more quickly than diesel-powered trains, allowing Caltrain to run more efficiently. In addition, because of their performance advantages, electrified trains will enable more frequent and/or faster train service to more riders".

[1]http://www.caltrain.com/projectsplans/CaltrainModernization/... [2] http://www.caltrain.com/Assets/Caltrain+Modernization+Progra...

Re: Analyzing Caltrain Delays

#15

Earlier quoted context omitted.

Electrified Caltrain is infinitely preferable to BART.

Why electrified vs normal caltrain? Will that decrease the variance or door to door time of using caltrain?

Faster acceleration. Each stop will cost less time, and Caltrain has a surprising amount of stops between SF-SJ (22 weekday) for its length (47 miles). You can see this effect already with the amount of express schedules that Caltrain has and their varying trip times.

Re: Analyzing Caltrain Delays

#16
post #5

Earlier quoted context omitted.

I can't help but feel that if there was a BART line where the Caltrain currently runs, things would be about a hundred times better than they currently are, on all fronts. Alas...

Electrified Caltrain is infinitely preferable to BART.

Not if it still runs at-grade and keeps killing someone every few weeks.

Re: Analyzing Caltrain Delays

#17

Seriously, need to break that vicious cycle: you get used to things going bad, people who run them get used to not delivering, breaking due process, posting unrealistic schedules, and BAM - now you think the problem can't be solved, only plotted. I don't remember last time when I have not seen a train at a station at scheduled time, and the place where I live doesn't expire confidence. When something is late, it gets…

To be (grudgingly) fair to Caltrain, a lot of things are perhaps indirectly out of their control-stuff like suicides (until you get gated platforms to stop people from jumping in front of Baby Bullets) and vehicles stopped on tracks are hard to predict. Likewise they are a victim of their own success-standing room only trains make boarding and unboarding longer than they have to be. Of course, Caltrain has put off el…

Vehicle and person hits cause exceptional delays, but not significantly more so than the string of breakdowns in February. They apologized for this, and seem to have fewer rush hour problems, so maybe this has improved.

They could do more to improve the standing room problem, which adds up quickly. My evening train is now perpetually 3-5 minutes late, which adds 10% to the runtime, due to the train in front being overcrowded. They are putting out new timetables for next month that they claim will improve this. Their fix is to move its departure time closer to the slow train in front, and add 3 minutes to the trip duration. Frustrating.

Re: Analyzing Caltrain Delays

#18
Data scientists blog about Caltrain data, come up with convoluted hypothesis about bias in sensors at two stations.

Commenter on blog notices that Caltrain is occasionally single-tracking between those stations due to a bridge replacement. [1]

"Data science" ends up with a bloody neck from Occam's razor.

[1] http://www.caltrain.com/projectsplans/Projects/Caltrain_Capi...

Re: Analyzing Caltrain Delays

#19

Earlier quoted context omitted.

Electrified Caltrain is infinitely preferable to BART.

Not if it still runs at-grade and keeps killing someone every few weeks.

It's not as if Caltrain is required to run at grade. It's just a historical artifact of how the system evolved. If we had the money and political will to replace Caltrain with BART, we'd have the money and will to create a grade-separated Caltrain.

What would be the advantage of BART over electrified, grade-separated Caltrain? I'm hard-pressed to think of one, and there's definitely one major disadvantage: the nonstandard rail gauge.

Re: Analyzing Caltrain Delays

#20

Data scientists blog about Caltrain data, come up with convoluted hypothesis about bias in sensors at two stations. Commenter on blog notices that Caltrain is occasionally single-tracking between those stations due to a bridge replacement. [1] "Data science" ends up with a bloody neck from Occam's razor. [1] http://www.caltrain.com/projectsplans/Projects/Caltrain_Capi...

The data was sound. They formed a hypothesis. They got a better explanation. Now they have a better hypothesis for the data anamoly. I don't think it's fair to fault them or to discredit the effort.
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