Transfer Penalties and the Community Process

In Seattle, there is an ongoing controversy over a plan to redesign the bus network along the principles proposed by Jarrett Walker: fewer one-seat rides to the CBD, more frequent lines designed around transfers to Link, the city’s light rail system. For some background about the plans, see Capitol Hill Seattle, Seattle Transit Blog, and the transit agency on a restructure specific to an upcoming Link extension to the university (U-Link), and Seattle Transit Blog on general restructure, called RapidRide+. The U-Link restructure was controversial in the affected neighborhood, with many opposing changes to their particular bus route.

Since the core of the plan, as with many restructure plans in North America, is to get people to transfer between frequent core routes more and take infrequent one-seat rides less, this has led to discussion about the concept of transfers in general, and specifically the transfer penalty. I bring this up because of a new post by Jason Shindler  on Seattle Transit Blog, which misunderstands this concept. I would like to both correct the mistake and propose why transfers lead to so much controversy.

The transfer penalty is an empirical observation that passengers prefer trips with fewer transfers, even when the travel time is the same. Usually, the transfer penalty is expressed in terms of time: how much longer the one-seat ride has to be for passengers to be indifferent between the longer one-seat trip and the shorter trip with transfers. For some literature review on the subject, see Reinhard Clever’s thesis and a study by the Institute for Transportation Studies for the California Department of Transportation.

Briefly, when passengers take a transit trip with a transfer, making the transfer takes some time, which consists of walking between platforms or stops, and waiting for the connecting service. Passengers weight this time more heavily than they do in-vehicle travel time. According to New York’s MTA’s ridership model, passengers weight transfer time 1.75 times as much as they do in-vehicle time. In other words, per the MTA, passengers are on average indifferent between a one-seat ride that takes 37 minutes, and a two-seat ride that takes 34 minutes of which 4 are spent transferring. Observe that by the MTA’s model, timed cross-platform transfers are zero-penalty. Other models disagree – for example, the MBTA finds an 11-minute penalty on top of a 2.25 factor for transfer time.

The transfer penalty can be reduced with better scheduling. Timed transfers reduce the waiting penalty, first because there is less waiting on average, and second because the (short) waiting time is predictable. When transfers cannot be timed, I believe countdown clocks reduce the waiting penalty. Walking between platforms or bus stops can be made more pleasant, and bus stops can be moved closer to train station entrances.

However, regardless of what the transit agency does, the transfer penalty is an average. Even for the same origin and destination, different people may perceive transfers differently. Any of the following situations can result in a higher transfer penalty:

  1. Heavy luggage. This also leads to bias against staircases, and often against transit in general and for cars and taxis. The waiting penalty does not grow, but there may be a significant penalty even for cross-platform transfers.
  2. Travel in large groups, especially with children. As an example, in comments here and on Itinerant Urbanist, Shlomo notes that ultra-Orthodox Jews, who travel with their large families, prefer one-seat bus rides over much faster and more frequent train rides. Families of 3-5 are also much likelier to drive in a family car than to take an intercity train or bus.
  3. Disability, including old age. This has similar effect to heavy luggage.
  4. Lack of familiarity with the system. This is common for tourists but also for people who are used to taking a particular bus route who are facing significant route restructuring. This can also create a large bias in favor of trams or trolleybuses, since their routes are marked with overhead wires and (for trams) rails, whereas bus routes are not so obvious.
  5. Reading, or getting other work done in transit. For longer intercity trips, sleeping is in this category, too. This tends to bias passengers against mid-trip transfers especially, more so than against start-of-trip and end-of-trip transfers.
  6. Seat availability. Passengers who get on a bus or train when it still has seats available may prefer to keep their seat even if it means a longer trip, and this shows up as a transfer penalty. This does not usually affect start-of-trip transfers (buses and trains probably still have seats), but affects mid- and end-of-trip transfers.

In contrast, people who are not in any of the above situations often have very low transfer penalties. In New York, among regular users of the subway who do not expect to get a seat, zero-penalty transferring appears to be the norm, especially when it’s cross-platform between local and express trains on the same line.

Usually, people in groups 3 and 4 are the major political forces against bus service restructuring plans. They’re also less willing to walk longer distances to better service, which makes them oppose other reforms, including straightening bus routes and increasing the average interstations in order to make bus routes run faster. This is also true of people in groups 1 and 2, but usually those are not inherent to the passenger: most disabled people are always disabled, but most passengers with luggage usually travel without luggage. The one exception is airport travel, where luggage is the norm, and there we indeed see more advocacy for one-seat rides to the CBD.

The key observation here is that even a route change that is a net benefit to most people on a particular origin-destination pair is sometimes a net liability to some riders on that pair. While it’s a commonplace that reforms have winners and losers, for the most part people think of it in terms of different travel patterns. Replacing a CBD-focused system with a grid leads to some losers among CBD-bound riders and winners among riders who travel crosstown; boosting off-peak frequency creates winners among off-peak travelers; straightening one kink in a bus route leads to losers among people served by that kink and winners among people riding through. The different transfer penalties are a different matter: even on the same origin-destination pair, among people traveling at the same time, there are winners and losers.

Solutions to this issue are bound to be political. The transit agency can estimate the net benefit of a restructure, and sell it on those grounds, but it’s not completely a win-win; thus some political process of conflict resolution is required.

In this particular case, the community process is reasonable. The main flaw of the community process is that the people who come to meetings are not representative of the body of riders and potential riders, and are especially likely to be NIMBYs. For example, on Vancouver’s West Side, the community meetings for the Broadway subway were dominated by NIMBYs who didn’t want outsiders (especially students) to have an easier commute to UBC, and not by people who could use the subway, often traveling through the West Side without living or working in it.

But the conflict when it comes to transfers is between groups of people who live in the same area. Moreover, there is no clear bias in either direction. Older people, who are usually more averse to change, are especially likely to show up to meetings; but so are transit activists, who are more informed about the system and thus more willing to transfer. People with intense familiarity with their home bus line are balanced out by people with familiarity with the system writ large. There is also no opposition of a widely shared but small benefit to most against a narrow loss to the few: instead, such reforms produce a large array of changes, ranging from major gains to major losses. Finally, frequent bus grids do not generate much transit-oriented development, unlike rail, which produces NIMBY contingents who are against transit investment on the grounds that it would lead to upzoning and new development (as in the above example from Vancouver).

The result is that here, political control can lead to positive outcomes, as the transit agency is required to consider the effect of change on many subsets of riders. Frequent grids really do generate losers, who deserve to be heard. In this case, it appears that they are outnumbered by winners, but the winners have as much of a political voice as the losers; there is no large gap between good transit and what the community thinks good transit is.


  1. Lewis Lehe (@LewisLehe)

    I think it’s hard to get past this issue without addressing bus bunching and headway regularity. People will be less averse to transfers once that is taken care of, especially if some can see the location of the second bus on their phones via GPS.

    • Alon Levy

      Yep. I should clarify that the MTA’s transfer-friendlier model still predates countdown clocks, bus arrival apps, etc. I’d be interested to see what the transfer penalty is for people who use Google Transit or similar automated direction systems to plan trips.

      • Adirondacker12800

        Stuff happens. What good is it to have Google tell me that the bus, which hasn’t left it’s terminal yet or even arrived at the terminal should be at my transfer point when I get there 22 minutes from now? Assuming I get to the transfer point 22 minutes from now.

        • michael.r.james

          I’m with Adirondacker. The BRT system in Brisbane has those electronic displays that countdown arrival of the next 6 buses, but users have come to be blind to them. On the most frequent semi-express buses (the most popular of course) they are just too often wrong, with what I call “ghost buses” counting down to zero without any bus arriving, followed by appearance of the next bus with new countdown at the bottom of the display queue. I believe the bus info is supposed to be live-GPS tracking so, go figure. Most of us think this kind of thing is totally related to how the management need good “on time” figures for their quarterly reports and they will generate that even if it needs ghost buses to do it! (There is possibly a quantum physics explanation that is beyond me.)

          I think the biggest issue with transfers is if both legs are bus. Their notorious unreliability, even in more reliable BRTs, make travellers extremely reluctant to use a 2 leg bus trip. I am assuming that the Seattle design involves transfer from bus to Link, and that Link has its own exclusive ROW and will be run at high-frequency? That should work and de-congest the system from too many buses. In the Brisbane BRT they have not yet grasped this solution and have severe bus congestion on the busway at several bottlenecks because they are trying to run buses very long distance.Take a look at this terrific pic of a queue of about 24 buses in a traffic jam (on BRT on bridge into & out of CBD):

          Jarrett Walker actually tweeted about this, saying “Why are attacks on busways always illustrated with pictures of where a busway is incomplete?” But the BRT is complete (those buses are not sharing road or bridge lanes with any other traffic, and though he may be referring to the traffic lights just out of pic, that is not the cause of the bottleneck because it extends over the intersection into the bus tunnel on the other side). (Oh, and most BRTs do have sections shared or intersected with regular street traffic–for the reason that the original rationale for building BRTs is that they are the cheapest option, so solving those pesky interactions is quite expensive.) Many of these buses would be found to be carrying few pax (esp. as many routes come from way up north of the city, thru the centre and then way down south!). The inner part of the busway needs to replace buses with hi-frequency LR and use buses only as feeder; these big busway stations could cope with both with little modification).
          Incidentally the sheer number of buses and different routes means the bus stations (the one shown in the background of the pic) allow stopping of 6 at a time, but any bus (route) can be at any stop, so it is a total shambles a lot of the time, and of course when most people are using the system.

          • Nathanael

            Jarrett’s a one-mode bus fanatic, unfortunately. It’s sad that he gets so much attention; he should never, ever be hired as a consultant because of his extreme pro-bus, anti-rail bias.

          • Brendan Dawe

            Apparently asking that buses be made to suck less and pointing out that streetcars are subject to a dubious mythology makes one a ‘one mode bus fanatic’

          • Max Wyss

            Jarrett Walker is pretty much mode-agnostic, meaning that he suggests the mode most suitable for the needed capacity and frequency. And that does mean “bus” with most of his clients. And his clients want something kind of “now”, and not in ten years.

          • Eric

            …and without a billion dollar expenditure on new rail that leaves transit no more effective than before.

          • Nathanael

            Nope. Jarrett Walker is a one-mode diesel bus fanatic. When you present evidence that rail, or even trolleybuses is superior for a given application, he downplays it and ignores it in order to advocate for buses.

            He’s done it repeatedly, to poor reviews in Minneapolis, to poor reviews in Wellington, to poor reviews in Brisbane….

            Find me a case where he’s actually recommended rail improvements. Seriously. Find one.

          • Nathanael

            “Jarrett Walker is pretty much mode-agnostic, meaning that he suggests the mode most suitable for the needed capacity and frequency. ”

            No, that’s what he *says*. But he’s lying. He repeatedly tilts the numbers to bias his recommendations against rail and against trolleybuses and in favor of buses.

          • Nathanael

            I suspect Jarrett doesn’t even realize he’s doing it. But he should, when he’s gotten serious pushback for his bad advice repeatedly.

            When a city comes in all a-fire with “We’ve got a big movement where people want to put in a streetcar”, does Jarrett say “Well, if you’re going to do that, you really need exclusive lanes”. No. He says “BUS BUS BUS BUS BUS BUS BUS BUS IS AS GOOD AS RAIL”, which is demonstrably untrue.

          • Nathanael

            Remember, Jarrett Walker thinks the non-functioning Brisbane Busway is the Greatest Thing Ever (he’s said so repeatedly) and touted it as a perfect example of a complete system where buses are better than rail. So now that it’s been shown that it doesn’t work right, *now* he claims it’s incomplete? Look back at what he said about it before.

            He’s a bus fanatic.

      • Lewis Lehe (@LewisLehe)

        Yes that’s worth studying. I know i’ve seen different travel cost coefficients for “with GPS map” vs “without,” but I have not seen transfer penalties.
        I still think the real boost will come from actual headway regularity via dynamic control of buses/vans. It is really a pretty cheap solution. They are working on it in Chicago, but I expect it will really be accomplished well in Ontario or BC first due to their effective bureacracy.

  2. Daniel HOdun

    Just as a reminder Alon that Page 2 of STB typically is to be taken with a grain of salt as anyone can post their ideas there and the ideas can be quite ill thought out. The posting to me spoke of subsidizing inefficiency and it makes no sense and the airline industry knows this one. If you have to have a passenger transfer versus having them on a non-stop, it costs you more. Yet sometimes the fare system says the transfer costs less than the non-stop.

    Irony isn’t it.

  3. Mark Lyon

    You didn’t mention the Anxiety Factor. That is the uncertainty I feel while waiting to make the connection. Especially during business travel. It’s a huge factor in my preference for a non-stop journey.

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  5. Fran Taylor

    We’re dealing here in San Francisco with a proposal that would force riders going to the county hospital to transfer onto a busy line that typically has difficulty squeezing on the wheelchairs and walkers used by many patients. In this case, the numbers affected may not be huge, but they represent some of the most vulnerable users of the transit system (Muni) and reveal potential obstacles to access to health care.

    Opponents aren’t NIMBYs or anti-transit at all, just trying to ensure that the poorest people in a city choking on wealth get consideration. This video doesn’t examine the technicalities, just the human face of this debate:

    • Andre Lot

      That would, or would not, be a problem of transportation of people with particularly serious disabilities. Don’t stick the bill to MUNI, but to the health care system. Nobody should be entitled to some specific bus route as if it was a divine right. So if that is the case, use the para-transit system to deal with the issue of patients too frail to use transit to reach the hospital.

  6. johndmuller

    My local bus route is a fine example of competing priorities. What was once a nice little local route that served my neighborhood well, became a ‘kink’ in a much larger route connecting cities in a county run bus system and has been rationalized by short-cutting through and bypassing a large portion of the potential riders – except for a token remnant of service following the original route with such an infrequent and irrational schedule as to be essentially unusable – and this as an offshoot of a line that otherwise provides decently frequent service. The powers that be in the bus bureaucracy have even expressed interest in further rationalizing the route to bypass the village center making it even less useful to local riders.

    Presumably, this kind of thing looks good in terms of minimizing end-to-end trip time and probably helps protect the schedule from delays due to curvier roads and greater congestion (not to mention the annoying time it takes to board and unload passengers who might want to go to these places). I doubt very much that there are very many people taking this bus end-to-end, especially as there are several other routes doing that same city pair, at least one of which appears to have a considerably faster highway.

    It seems that they need to face up to the fact that they have two different constituencies on some of these routes and just run two different buses. People can choose more local version if they want to go places on the ‘kinks’, or transfer to the more direct version if they want to make better time. Unfortunately, if you make these long routes, the majority of riders are not interested in local segments in someone else’s town, so the politics tend to favor cutting them, and you end up with buses that don’t serve anyone really well.

    • Nathanael

      An example of the importance of figuring out who your customers are and what they want. Always a good idea and weirdly not done often enough.

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  8. Anthony

    I believe the transfer penalties in developing countries (in my case, Brazil) are much larger than your experience. Time tables are very rarely precise (if ever), allowing for a lot of risk in estimating travel times, with high fluctuation if the passenger misses the “next” bus in his transfer. Also, transfers also increase risk of assault, specially if travelling alone, as some bus stops can be located in a dangerous area.

    I also believe that some cities have increased tranfer penalties: those where the information economy prevails and where gadgets such as smartphones with high speed mobile internet connection have high penetration. Direct rides are more productive (or less inneficient from the rider’s perspective) as time can be effectively used. That makes the transfer process more costly, as time used when transfering is very inneffective.

    • Eric

      In my experience, when a bus/train arrives I can usually hear it, so I spend the transfer time looking at my phone/laptop just as I would while riding.

      Of course this depends on the location – whether it is quiet and safe enough.

      • sonamib

        Well, in some places, you just can’t do it, because you have to catch a specific bus. Since Anthony brought up Brazil, let me talk about my experience taking the bus to the university in Rio de Janeiro*. My stop was in a major boulevard, and 10+ lines used it. At any given moment, there were two or three buses arriving, but mine was an infrequent one which only came about once every 6-10 minutes. Not missing my bus was a mentally intense activity, which required looking at the line numbers of all the dozens of buses coming through and then waving at the driver of my bus to actually stop (that might be hard when it’s behind yet another bus). Doing that more than once per trip would be hell.

        Now, Rio de Janeiro does have a big transit problem. Rapid and high-capacity transit is severely lacking. And bus lines need some heavy consolidating. To be fair, things are changing, there’s a new BRT and new metro stations, and bus lines are being consolidated but there’s still a long way to go.

        *I grew up in Brazil, I now live in Belgium.

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