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by rahulnair23 4801 days ago
Hi, I'm from the IBM Research team who worked on this.

The reduction is in total system-wide journey times in passenger-minutes (travel time + expected waiting time). The model makes underlying assumptions on how people arrive at stops to do their trips, and how they choose paths through the network. The wait times are therefore related to frequency of services.

The statistic is also broken down by each route what happens when the changes (new routes or extensions) are implemented. For some routes, you see increase in ridership (on account of better connectivity), and on some you see decreased ridership (since the new routes offer more competitive paths through the network).

2 comments

Thanks. Really interesting work.

Are you allowed to share some of the data ? If so:

Does the time includes time to walk to bus station or an estimate?

Is there some histogram of time saved per passenger ? or even something like X% of passengers save a big amount of time ?

Do you have a way to estimate time save by adding routes or alternative transport(like jitneys) before making the change?

Those are interesting, but i also think if some of this data was available(like for example big time saving for some part of the population), this would have better media coverage.

Yes travel time includes time to walk from the Cell tower (considered the "source" and "sink") to the stops.

We could generate passenger level stats for the sample we observed, but have presented it at the route level for now, since its targeted towards operators.

Yes, the improvements reported are from adding of new routes (the article title suggests that we "redrew" current routes). The new routes are generated from "frequent" patterns we see in the data. Haven't looked specifically at alternative modes, although there are several reasons to discourage jitneys.

Based on the research, how different is the proposed more-efficient bus routes from the already existing bus routes?

Or more to the point, how correct (or incorrect) were the urban planners in their choice of bus routes?

More information like how large the bus route system had grown since its inception -- for example did it grow organically over time in small growth spurts or was it in larger controlled route expansions/reductions -- would be useful as well.