What would really be interesting to play with is the real-time location of each train. The MTA must have it. I wish they would publish it somehow.
I'd love to build a city-wide visualization of the train traffic that shows where it's backing up, where it's flowing smoothly, etc. It probably wouldn't be very useful for me as an NYC commuter, but purely as a visualization it would really be something.
They do have real time information for the A-division (numbered trains). The B-division trains are, however, a dogs breakfast with no central monitoring or dispatch. There are plans afoot to spend a couple of billion dollars to perform a dispatch upgrade for BDiv -- but given the generally strapped nature of the MTA, I wouldn't hold my breath for the information to be made available anytime soon.
Sort of. The 7 is A division and has no data, and the L is B division and has data.
Plus, who needs realtime train position data when you can just listen for those helpful manual announcements like "An uptown express train is approaching W 4th St."
London makes this information available, allowing the sort of visualisation you suggest [1]. As you say, it's interesting but not that practical from a commuter's perspective.
You could definitely just interpolate between arrival times for stations. Add in a little historical averaging for the same routes (maybe broken out by hour / day of week) and I bet you could get pretty close to accurate.
I'd love to build a city-wide visualization of the train traffic that shows where it's backing up, where it's flowing smoothly, etc. It probably wouldn't be very useful for me as an NYC commuter, but purely as a visualization it would really be something.