Pulses (Hoisted from Comments)

Robert Jackel asked me an excellent question in comments: what is a pulse? I’ve talked about timed transfers a lot in the last almost 10 years of this blog, but I never wrote a precise definition. This is a critical tool for every public transportation operation with more than one line, making sure that trains and buses connect with as short a transfer window as possible given other constraints. Moreover, pulse-oriented thinking is to plan capital investment and operations to avoid constraints that make transfers inconvenient.

When are pulses needed?

Passengers perceive the disutility of a minute spent transferring to be more than that of a minute spent on a moving vehicle. This is called the transfer penalty and is usually expressed as a factor, which varies greatly within the literature. In a post from 2011 I quoted a since-linkrotted thesis with pointers to Boston and Houston’s numbers, and in a more recent post I found some additional literature in a larger variety of places, mostly in the US but also the Netherlands. The number 2 is somewhere in the middle, so let’s go with this.

Observe that the transfer penalty measured in minutes and not in a factor is, naturally, larger when service runs less frequently. With a factor of 2, it is on average equal to the headway, which is why it is likely the number is 2 – it represents actual time in the worst case scenario. The upshot is that the value of an untimed transfer is higher the higher the frequency is.

I used the principle of untimed transfers and frequency to explain why small subway networks do not look like small bus networks – they have fewer, more frequent lines. Subway lines that run every 3-4 minutes do not need transfer timing, because the time cost of an untimed transfer is small compared to the likely overall trip time, which is typically in the 15-30 minute range. But the lower the frequency, the more important it is to time transfers. Thus, for example, Berlin times the U6/U7 transfer at Mehringdamm in the evening, when trains run every 10 minutes, but does not do so consistently in the daytime, when they run every 5.

But note: while the value of an untimed transfer is higher at higher frequency, the value of a timed transfer is the same – it is zero-penalty or close to it no matter what. So really, the relative value of timing the transfer decreases as frequency increases. But at the same time, if frequency is higher, then more passengers are riding your service, which justifies more investment to try to time the transfer. The German-speaking planning tradition is the most concerned with transfer timing, and here, it is done commonly at 10 minutes, occasionally at 5 minutes, and never that I know of at higher frequency.

Easy mode: one central station

If all your buses and trains serve one transit center, then a pulse means that they all run at the same frequency, and all meet at the center at the same time. This doesn’t usually happen on urban rail networks – a multi-line urban rail system exists in a high-ridership, high-frequency context, in which the value of serving a mesh of city center lines is high, and the cost of bringing every subway tunnel to one location is high. Instead, this happens on buses and on legacy regional rail networks.

The pulse can be done at any frequency, but probably the most common is hourly. This is routine in small American towns with last-resort bus networks serving people too poor or disabled to drive. Two and a half years ago a few of us on Transit Twitter did a redesign-by-Twitter of the Sioux City bus network, which has ten bus routes running hourly, all pulsing in city center with timed connections. A similar network often underlies the night buses of a larger city that, in the daytime, has a more complete public transport network, such as Vancouver.

Even here, planners should keep two delicate points in mind. First, on buses in mixed traffic, there is an upper limit to the frequency that can be timetabled reliably. The limit depends on details of the street network – Jarrett Walker is skeptical that timetabling buses that run every 15 minutes is feasible in a typical American city, but Vancouver, with no freeways within a city and a rich arterial grid, manages to do so every 12 minutes on 4th Avenue. A half-hourly pulse is definitely possible, and even Jarrett writes those into his bus redesigns sometimes; a 20-minute pulse is probably feasible as well even in a typical American city. The current practice of hourly service is not good, and, as I point out in the Sioux City post, involves slow, meandering bus routes.

The second point is that once the takt is chosen, say half an hour, the length of each roundtrip had better be an integer multiple of the takt, including a minimal turnaround time. If a train needs 5 minutes to turn, and runs half-hourly, then good times for a one-way trip from city center are 10, 25, 40, 55 minutes; if there is no turnaround at city center, for example if there is through-running, then half as many turnarounds are needed. This means that short- and long-term planning should emphasize creating routes with good trip times. On a bus, this means straightening meanders as needed, and either extending the outer end or cutting it short. On a train, this means speedup treatments to run as fast as necessary, or, if the train has a lot of spare time, opening additional infill stops.

The issue of branching

Branches and pulses don’t mix well. The ideal way to run a system with a trunk and branches is to space the branches evenly. The Berlin S-Bahn runs every 3-4 minute on the Stadtbahn trunk and on the North-South Tunnel, mixing services that run every 10 and 20 minutes at roughly even intervals. In such an environment, timed transfers in city center are impossible. This is of course not a problem given Stadtbahn headways, but becomes serious if frequency is sparser. A one-trunk, two-branch regional rail system’s planners may be tempted to run each branch every half hour and interpolate the schedules to create a 15-minute headway on the trunk, but if there’s a half-hourly pulse, then only one branch can participate in it.

This is visible when one compares S-Bahn and RegionalBahn systems. High-frequency S-Bahn systems don’t use timed transfers in city center, because there is no need. I can get from Jannowitzbrücke to Ostkreuz without consulting a schedule, and I would get to the Ring without consulting a schedule either, so there is no need to time the crossing at Ostkreuz. There may be sporadic transfer timing for individual branches, such as between the S9 branch of the Stadtbahn, which diverts southeast without serving Ostkreuz, and the Ring, but S9 runs every 20 minutes, and this is not a pulse, only a single-direction timed connection.

In contrast, RegionalBahn systems, running at longer ranges and lower frequencies, often tend toward timed transfers throughout. The tradeoff is that they don’t overlie to create high-frequency trunks. In some cases, trains on a shared trunk may even platoon, so that all can make the same timed transfer, if high trunk frequency is not desired; this is how intercity trains are run on the Olten-Bern line, with four trains to a platoon every 30 minutes.

Medium mode: dendritic networks

A harder case than the single pulse is the dendritic network. This means that there is a central pulse point, and also secondary pulse points each acting as a local center. All cases I am aware of involve a mainline rail network, which could be S-Bahn rather than RegionalBahn, and then bus connections at suburban stations.

Already, this involves more complex planning. The reason is that the bus pulse at a suburban station must be timed with trains in both directions. Even if planners only care about connections between the suburban buses and trains toward city center, the pulse has to time with inbound trains for passengers riding from the suburban buses to the city and with outbound trains for passengers riding from the city to the buses. This, in turn, means that the trains in both directions must arrive at the station at approximately the same time. A few minutes of leeway are acceptable, since the buses turn at city center so the connection always has a few minutes of slack, but only a few minutes out of what is often a half-hourly takt.

Trains that run on a takt only meet every interval equal to half the takt. Thus, if trains run half-hourly, they can only have suburban pulses every 15 minutes of travel. This requires planners to set up suburban pulses at the correct interval, and speed up or sometimes slow down the trains if the time between suburban nodes. Here is an example I’ve worked on for a Boston-Worcester commuter train, with pulses in both Framingham and Worcester.

Hard mode: meshes

The next step beyond the dendritic network is the multi-node network whose graph is not simply connected. In such a network, every node must have a timed transfer, which imposes considerable planning constraints. Optimizing such a network is an active topic of research in operations and transportation in European academia.

Positive examples for such networks come from Switzerland. Large capital investments are unavoidable, because there’s always going to be some line that’s slower than it needs to be. The key here is that, as with dendritic networks, nodes must be located at consistent intervals, equal to multiples of half the headway, and usually the entire headway. To make multiple timed transfers, trains must usually be sped up. This is why pulse-based integrated timed transfer networks require considerable planning resources: planning for rolling stock, infrastructure, and the timetable must be integrated (“the magic triangle”) to provide maximum convenience for passengers connecting from anywhere to anywhere.

58 comments

  1. Nathan Davidowicz

    In Vancouver BC most bus routes used to operate every 10 mins or better throughout the daytime. It was cutback when rail transit started in 1986. Vancouver could have an excellent bus service if the missing links of the GRID system are completed so that anyone is within 400 m of North-South and East-West bus stop. This is the only way the city can increase the mode split of transit but the staff does not understand that. Metro Vancouver rides per capita are around 100 while Montreal and Toronto with a similar population are around 200.

    • Rico

      The 80s were the start of my transit awarenesses in Vancouver but a couple of points to your comment. Bus service hours were not cut following the introduction of Skytrain. It was increased (but reorganized), that is how they got buy in from the union. Increased bus service is a big part of Vancouver’s transit success compared to say Portland. You complain about mode split but Vancouver probably had the biggest transit mode share increase in North America from 1986 to now. Also Vancouver is not even close to being similar in size to Toronto. It’s even significantly smaller than Montreal.

      • Nathan Davidowicz

        Most population increase over the last 50 yrs has been in the faraway suburbs of Metro Vancouver. The mode split figures given by TransLink are not accurate. While overall transit ridership increased the actual rides per capita increased very little. The number of cars increased faster than the population increase. Many people are blindfolded by media reports from TransLink. COVID has set us back by at least 4 yrs and in the meantime, TL will continue wasting our money.

        • Rico

          Ignore the double post below. I meant to reply here. Sorry for the diversion off the pulse topic but I would like to correct a few of your statements. First off for transit trips per capita in Vancouver increased similar to what would be expected compared to Statistics Canada increases in transit mode share (which were probably the highest in North America). So the stats are in agreement and I think we can all agree Stats Can is unbiased (although it measures journeys to work not total trips). I don’t understand why people think a transit agency would be cooking the books especially since a lot of the stats are driven by the census, not the transit agency and now with smart cards the agency (and its auditors) should know exactly how many rides were taken and paid for. I know Vancouver has a well known transit conspiracy blog that advocates that Translink (the Vancouver transit agency) is basically the devil and some sort of propaganda machine but I would not expect anyone outside of that blog to fall for that (Translink, fudging rising transit use since 1986…you’d think someone would have noticed). Also note auto mode share for Vancouver decreased (although not massively %age wise), not increased (the number of cars per capita did increase as well, but I assume this is due to rising affluence?). I should also point out transit trips per capita for Toronto are not about 200, they were 187 in 2016 and Metro Vancouver was not about 100 but 146 and that Metro Toronto is more than twice the size of Metro Vancouver. Slamming your local transit authority is a time honoured practice, but please stick to real complaints. Complaining about cut backs to bus hours when bus service hours increased (not just by a little), complaining about transit mode share when transit mode share improved more than any other comparable North American city, complaining about auto mode share when it went down (pretty rare in North America) The complaints in your comments are actually areas where Vancouver is a North American leader. I know we should be setting our sights higher than that but…maybe complain about the projected costs of the Broadway subway relative to earlier lines or the decision to build the Evergreen line before Broadway.

          • nathanarticulated

            Rides per capita in Metro Vancouver was 104 in 2019. ( 272 M trips population 2.61 M ) you are right that the Evergreen Extension should have been built after the Broadway Subway.

          • Rico

            I used boarding as I could not find trips, where did you find the annual trips?

  2. Eric2

    It seems to me that pulses in cities are essentially useless in the most common circumstance – when the two routes cross each other at an intermediate station, rather than a terminal, for both lines.

    This is because at an intermediate station, you want to transfer in both directions. Let’s say route A reaches the station at 1:30 exactly. If you want to allow 2 minutes for all passengers to transfer, then route B must arrive at 1:28 (to allow transfers to A) and wait in the station until 1:32 (to allow transfers from A). So every single passenger on route B must wait 4 minutes in order to save transferring passengers time waiting in the station!

    In reality it’s worse than that, because timings are unreliable. Let’s say there is a 1 minute uncertainty in route A (rail with separate ROW), and 5 minute uncertainty in route B (bus with traffic and/or lights to deal with). Then you must provide a margin for A coming early and B late, or the reverse. If A is scheduled for 1:30, B must arrive by 1:22 and leave after 1:38. A 16 minute wait for all passengers, just to save some time for transferrers! Better not to attempt this pulse at all, unless route B has an ultra low frequency like once every 2 hours.

    If route B terminates at the junction, you can schedule route B to arrive (finish its route) at 1:22 and leave (begin its route) at 1:33, and the pulse works. But it doesn’t work if route B through runs.

    In real life I only know of one location that attempts an urban pulse with through-running lines: Längenfeldgasse station on the Vienna metro, where two metro lines (=grade separated, few delays) have a cross-platform transfer (=low transfer time), and one waits for the other to arrive. Pretty much anywhere else, the schedule uncertainty and transfer time make this impossible.

    • Alon Levy

      Berlin has a similar setup at Mehringdamm. At Wittenbergplatz, it’s even fancier and timetables the trains for minimum transfer times in all directions, though it’s necessarily not zero-penalty since the wrong-way transfers are not cross-platform.

      The general problem you describe is why grid routes don’t pulse, and why circumferential lines connecting to many radials can’t pulse either. So in the daytime, in a large city, you’re not going to pulse, only have a sporadic timed transfer on the subway. But at night you probably still want some transfer timing on the bus network. And the regional rail network of your large city should have some suburban pulses.

      • Kamoro

        I think you could still time transfers on a grid, but not in the sense that trains from all directions arrive at the same time. Instead, you could do a staggered arrival like follows: vehicles from line 1 arrive at :00, :15, :30, :45, vehicles from line 2 arrive at :07, :22, :37, :52. Such a setup allows more wiggle room for delays even in a mesh. You have to wait half the headway, so it wouldn’t work for 30 minute headways, but it would provide consistency in travel time. As far as time-space geometry, it should theoretically fit perfectly on a rectangular grid, but once there are irregularities, then things might get messy.

        • Alon Levy

          This isn’t done on a grid, because for it to work, grid points have to be spaced an integer multiple of half a headway apart, which is too onerous a requirement. If you do this not on a grid but at one key station, then you don’t have to stagger – you can hold the trains for 2 minutes so that people can make an everywhere-to-everywhere transfer.

  3. Allan Rosen

    I am surprised you do not mention a financial penalty for transferring as we have in New York City. Although you can now transfer between buses and buses and subways without financial penalties, there are limitations. There is talk of extending this to rail, but it’s only talk. There is no limit to the number of subways you can take, but you can only transfer to or from one bus for the same fare. So if you need a train and two buses, or a bus to a train to a bus, which sometimes is quicker than taking two buses, it cost you double fare. Also, it took the NYCTA and it’s successor about 50 years until they allowed bus subway transfers. It took over 70 years after private bus companies were dissolved to allow transfers between the routes of these companies unless the companies had agreed in the 1920s to allow those transfers. Only in rare cases, could you take three or more buses for one fare. In my 1972 Masters thesis, I pointed out one case in Brooklyn where you could ride 14 buses for a single fare. That’s how illogical the transfer system was in New York City. It would be interesting to find out if this was unique here or existed or exists in other cities.

    The major reason for not allowing timed transfers so someone could complete several errands on one fare, which would encourage mass transit usage, is the fear that someone could make a round trip with one fare and therefore a loss of revenue. That is the same reason why it took so long to allow transfers between all bus lines and between modes. So although waiting to make a transfer is an impediment, I believe the financial penalty is greater. In areas where the routes are outdated and multiple transfers are required for relatively short trips, usage of car services, or Uber like services are greater. That is never considered each time the MTA raises the fare every two years, which just increases the burden of a double fare.

    • Matthew A da Silva

      This could be easily solved if tap to exit became the norm in NYC – but for some reason OMNY is only set up for tap to enter. With tap to both enter and exit, like they have in London, the system can keep track of all of your transfers, and charge you appropriately if you take a round trip.

      • Alon Levy

        This could also easily be solved without it and even without systemwide POP – just make it a 2-hour trip and take the hit on people bundling a short roundtrip into one fare (those are not the trips you want to extract maximum revenue from).

        • Herbert

          Berlin single trip tickets are technically speaking “two hour one direction” tickets. There are occasionally calls to remove the “one direction” restriction, but they hardly ever go anywhere…

          • Alon Levy

            I don’t know if the ticket controllers even check the origin station here. The tickets do print it but I don’t think the controllers look? And even then there are some edge cases involving the Ring that are legal in both directions on the same origin station.

        • Allan Rosen

          I agree. Two hours from entering the system until the last transfer, or maybe even 90 minutes during frequent service hours. Much fairer for someone making a very long trip to pay a double fare than someone making a short trip just because three vehicles are involved. I have sent in testimony to this effect for at least the last two fare hike considerations and it is always ignored. Fairness is not a big thing for our MTA here.

          • Richard Mlynarik

            There shouldn’t be “directional” tickets in an urban system.

            Time-limited (1hr/2hr/24hr/3days/7days/30days/365days … whatever) paired with zone-limited is simple and consistent and customer-friendly and just works. “Is this ticket valid NOW and it is valid HERE?” is all that needs to be considered or verified. How and where the ticket-holder got to “here and now” and where they are heading are irrelevant and, in fact, nobody’s business.

            (And yes professional statistical sampling is more than good enough for service planning — full-on 100% surveillance insane drowing in data overkill.)

          • Sascha Claus

            And yes professional statistical sampling is more than good enough for service planning — full-on 100% surveillance insane drowing in data overkill.

            Only if professional statistical sampling is able to deliver data like reason for travel, willingness to take an earlier/later train, means of travel to/from stop (foot, bike, car, etc.) as good or better than smart cards! (Might contain traces of irony.)

    • Richard Mlynarik

      The major reason for not allowing timed transfers so someone could complete several errands on one fare, which would encourage mass transit usage, is the fear that someone could make a round trip with one fare and therefore a loss of revenue. That is the same reason why it took so long to allow transfers between all bus lines and between modes

      The Anglosphere (and the infection has spread, eg to Holland) will never be allowed To Have Nice Things, because Somebody Somewhere May Be Getting Away With Something, and therefore Something Must Be Done.

      Innumerates. Sociopaths. Ugh.

  4. df1982

    An excellent post, but I have a couple of questions:
    1. how do you factor in variable journey times for buses in mixed traffic running to a pulse? I.e. if in clear traffic you have a 25-minute journey time (which gives you a neat pulse), what happens if the travel time blows out to 31 minutes or more in rush hour, and so you lose the pulse? This is generally not an issue for trains, but this kind of variability is pretty normal for buses in urban areas, and short of bus lanes (which would probably not be done for a half-hourly service) it’s hard to do anything about it.
    2. do you really think lines should be slowed down to accommodate pulses? Would it really be advisable to make everyone’s service slower, in order to make the pulse work better? Couldn’t you just have a pulse with a wider spread to it?

    • Diego

      One way or the other, you have to slow down a too-fast train if you want it to make a pulse. If it arrives early and departs early then connecting passengers from other services cannot board the train, and will have to wait for the next pulse. If you want those passengers to be able to make the connection, you’ll need to hold the train a long time in the station. But that’s a waste of time, you might as well add a few infill stops beforehand so that the train doesn’t arrive early to the pulse.

      The alternative is to speed up the train enough so that it can make an earlier pulse! If there’s a pulse every 15 min, you can try cutting a 40′ travel time to 30′ instead of increasing it to 45′. But this isn’t always possible.

  5. Herbert

    Several cities have the issue that the “logical hub” for intracity (and suburban bus) transportation doesn’t necessarily align with the main station. Usually the distance is “only a few blocks” but it’s still too far to walk and trying to have both be served by pulses is awkward.

    Off the top of my head, I can think of Bayreuth (“ZOH” near main shopping district, train station somewhat outside) Nuremberg (“Plärrer” the historic interchange point and still the only point where all U-Bahn lines meet apart from main station – the Plärrer-Main Station connection is straightforward on the U-Bahn but needlessly complicated on the tram or bus), Dresden (“Postplatz” is both an important day hub and THE night hub of both trams and buses)

    What would the solution in cases like that be? Simply run all buses at ten minute (or better) headways and hope for the best? What about at night? (Nuremberg notably has no night service during the week whatsoever and as a “Covid-19 measure” the weekend night buses haven’t run in a year)

    • Sascha Claus

      Ahh, really big cities you mentioned … imagine how it must be in even smaller towns! You can always force passengers to bite the bullet and wait for a bus to the “logical hub” and change there again. If you don’t like that and all routes terminate in the centre, you might be able to squeeze all routes into two funnels which approach from opposite directions:
      One bundle passes through the logical hub and terminates at the station, the other one passes by the station and terminates at the hub, with both processions meeting in the middle.
      But it is really nessessary to have a pulse at the station, if the trains aren’t pulsing there?

      • Herbert

        Why would the trains not be pulsing at the station?

        Despite Bayreuth lying a bit awkwardly to the rail lines due to weird 19th century decisions (which may once more be entrenched if they indeed electrify Nuremberg-Hof but not any connection to Bayreuth) it does have rail lines in multiple directions.

        Nuremberg and Dresden of course even more so. In fact, one of the first two train stations in Germany (the other being in Fürth) was at the Plärrer. But that railway is almost a century since shut down – couldn’t compete with the tram. And the tram has in turn been replaced by the U-Bahn…

        • Sascha Claus

          Why would the trains not be pulsing at the station?

          Because the town lies awkwardly off to the side of a pulse, like Torgau or Oschatz? Or somewhere along a line between two pulses, like Meißen? (Though I didn’t check how all these would fit into a Dtl.-Takt.)

          (which may once more be entrenched if they indeed electrify Nuremberg-Hof but not any connection to Bayreuth)

          One could be forgiven for expecting this problem solves itself with an Alex Leipzig – Hof – Regensburg – Munich and a similar train Dresden – Hof – Nuremberg, which would to share the lines south of Hof naturally between themselves and getting the required infrastructure as needed …

  6. Robert Jackel

    So do pulses then require significant dwell times at the central station? Like, 2-3 minutes? People have to get off the bus, go up the stairs, etc. to the train

      • fjod

        Do you know how this works with journey planning apps? I know a barrier to introducing better timed transfers for trains in the UK is that there is a 5-minute minimum transfer time programmed into these, and journey planners will not show 1-, 2-, 3- or 4-minute connections.

          • fjod

            I am aware – but if you don’t know what connections you’re trying to make in advance, specifying transfer time doesn’t help.

          • Matthew Hutton

            The 5 minute general minimum is with the national rail website/apps. The tube is separate.

            I believe at one point Georgemas Junction on the far north line in Scotland had an official 1 minute interchange time in the timetable – I guess because the train would always wait.

          • fjod

            Yes – and, adding to Matthew Hutton’s point, the tube largely doesn’t run to passenger-facing timetables and so transfer times are quite ad hoc and vary between journey planners. I was indeed talking about the mainline rail system, on which timed transfers could in many places be of some value but would be hampered by this 5-minute rule.

        • Sascha Claus

          I assume you simply tell the journey planning software how much time is needed for each individual station? Or you take a blanket 3min and only tell the software if it’s more. The problem starts if you have these times differing by time of day or day of week, like 4min default and 1min during late night service because then the train always waits (like the Georgemas Jcn example).

  7. fbfree

    Dendric pulsed systems can be difficult to navigate for tourists. If you miss a connection due to poor navigation, language barriers, or inability to make the fare, you end up missing the timed transfer and have a worst case wait for the connection. I wonder if this type of experience has led to some of the derision encountered in exporting transit operation ideas across language barriers.

    • Richard Mlynarik

      pulsed systems can be difficult to navigate for tourists
      Does anybody really care what “tourists” “think”?

      If so, WHY?

      If so, why aren’t they thinking about anything of actual value to the overwhelming majority of actual humans?

      • Herbert

        In most major cities at least some of the communication is at least bilingual. Like “next stop main railway station” or some such. That’s of course easier for printed stuff and machines than for announcements

      • Henry Miller

        Not tourists, first time riders. The person who just moved into town. The person who has seen the bus from his car and keeps thinking I wonder if I actually could take that to work (not yet thinking about selling the car). When it is all new things are hard. Even if you know you need to transfer, you need to figure out where your.next ride is parked and make sure you don’t get on the wrong direction.

        The vast majority of your riders know this already and will be headed the right way when the doors open, but the new person will be a bit confused and so last off (when first is best for more time ), and then looking around for signs of where to go reading them all even though most won’t tell the right thing. What is needed is you go that way instead most say a route name.

        Tourists have similar problems, and once things are running more common so if they can do it the local who finally tries the system can.

        • Onux

          Without a dendric pulsed system EVERY tourist is faced with a worst case wait for the connection, regardless of which stop they use, because the busses will not be timed to meet the trains or vice versa.

          @Henry Miller: I am not sure if you are saying dendric pulsed systems are bad or will depress ridership because of the difficulty for first time riders, but the fact is they are easier for first time riders and lead to higher ridership. First, empirically the Swiss systems that use it have some of the highest transit mode shares in the wealthy world, despite being small metros.

          Second, the “new things are hard” applies to everything (including driving; which exit to take, where is there parking, one way streets, etc.) and isn’t unique to transit.

          Third, dendric pulsed systems make the first time ride EASIER. The first part of the first ride is likely getting on a bus. With a dendric pulse it is guaranteed the bus will stop (and everyone will get off) at a train station with the train waiting. This is the easiest possible transfer for a first time rider to make and understand (no wondering “does this bus go to the train station?”, no getting off at an empty train station wondering when the train arrives). Coming back all the customer has to do is get off at the same train station and it is guaranteed the bus home will be waiting, ideally in the same spot (at worst, if there are through routed busses, directly across the street). Once again this is the easiest possible system for a new rider to learn.

          • Henry Miller

            I’m saying ease of use makes a difference. Hard to navigate systems depress ridership, easy to navigate increases ridership – it is about ensuring people think they can figure it out from the timetable, and then ensuring once they try transit they get around. Different people have different pain tolerances. Those who cannot drive at all will tolerate a lot worse of a system vs the rich who are going to keep their luxury car anyway.

            There are lots of to solve the problem, some better than others, some cheaper than others. Often architects win awards for beautiful buildings that are completely unusable, a ugly utilitarian building where the money went to ease of transfers can make it much easier for everyone to get there – in the best case you might be able to allow less time for transfers which is very helpful. Alon is rightfully commenting on how much money is spent on stations, but we need to be careful to keep the good expenses.

          • adirondacker12800

            You have to understand that a significant fraction of people who complain it’s too hard to use are saying that because they realize it’s impolite to say “Me? Mix with the commoners? Surely you jest” and find some excuse that isn’t as rude.

          • Sascha Claus

            Without a pulsed system not every tourist is faced with a worst case wait—they could also coincidentially stumble upen a perfectly short connection, or an impossibly short connection or anything in between.
            But IME, tourists aren’t as obsessed with time as commuters: they do this once and should account for something going wrong anyway. If the service is frequent, a missed connection doesn’t mean you’re stuck until the next day.
            Commuters do this everyday, and having generously padded transfer eats into their free time _everyday_ and that quickly adds up.

        • Alon Levy

          The first time I rode BART to Berkeley and used the timed transfer, I made it fine. The timed transfer is clearly shown on the map, and is visible from the platform. The more complex pulsed transfers are announced as well – the conductor of a Swiss intercity train announces track numbers for connections a few minutes before the train gets to the station.

          • Matthew Hutton

            The London Underground has put a lot of thought into the signage so it is clear for tourists (as people stopping and getting confused doesn’t help with navigation).

            Also buses can either have stop announcements in local/English or in poor countries you have a conductor who finds an English speaker on the bus for you.

            So to the extent these are problems they can be resolved.

          • fjod

            in the Netherlands this is displayed on a screen – easily understandable by those who don’t speak Dutch (and gives you peace of mind for delays, platform alterations etc when you already know what connection you’re getting). 100% a solvable problem.

          • Henry Miller

            Your first time riding Bart isn’t relevant as you were experienced elsewhere and so while Bart was new, the rest of riding transit is normal. You already knew the common things to look for. Or at least so I guess – I don’t know your personal history well enough to be sure.

            The first time I rode the bus in my town I completely missed it the first two times before I figured out when it came. (one-seat ride so no transfer issues to worry about). It took me a few months of seeing a bus as I drove to work every day before I decided I really should try it, and then a few more months of cautious research before did (total time on research wasn’t much). Previously my experience with transit was either school (easy to use, but much more limited), or attempts where I gave up because it wasn’t possible (either didn’t go where I wanted to, or technically did, but not anywhere close to a useful schedule), so I was very nervous.

          • Herbert

            Most of the world has school buses that are – at least in theory – open to fare paying non schoolkids. Indeed in some rural areas the only “public transit” are those “thinly discussed school buses”…

        • Matthew Hutton

          The other issue is that if you don’t make the interchanges efficient it is difficult to make public transport time competitive with driving.

  8. Rico

    Sorry for the diversion but I would like to correct a few of your statements. First off for transit trips per capita increased similar to what would be expected compared to Statistics Canada increases in transit mode share (which were probably the highest in North America). So all of the official stats are in agreement and I think we can all agree Stats Can is unbiased. Also note auto mode share for Vancouver decreased not increased. I should also point out transit trips per capita for Toronto are not about 200, they were 187 in 2016 and Metro Vancouver was not about 100 but 146.

  9. Nilo

    What’s the optimal station layout for one of these big rail based pulses?

    A through station with a plethora of platforms?

    • Eric2

      Cross platform transfers between the two busiest lines+directions.

      Other than that, you need stairs/elevators, as short and simple and numerous as possible.

      • Eric2

        I realized you can get cross platform transfers between more than 2 lines, to a certain extent.

        For example, if you have three lines (A,B,C) you can use the following layout where |=track, O=platform:
        |O|O||O|O|
        Where the tracks from left to right are A,B,C,C,B,A.

        So you have cross platform transfers from lines A-B and B-C. Though not A-C.

        B should be the busiest line here, both because all its transfers are cross platform, and because it has a “Spanish style” setup which decreases its dwell time.

        Obviously you need lots of curves and flyovers to get the routes to line up in the right order – it might be cheaper/simpler to give up on the cross platform transfer and have the lines cross each other at 90 degrees and make all transfers go by stairs/elevator.

        • Sascha Claus

          A 90° station (or any other angled crossing) without intermediate transfer floor practically restricts passenger flow to one point per platform pair—at the point where they are above each other. Putting the tracks in parallel (or at a sharp angle like 30°) allows to have multiple crosswise tunnels/bridges spaced along the length of the platforms.
          Though in practice it is usually dictated by the orientation of the existing lines, which might have been built 100 years ago to enable track connections between lines and to fit in a goods yard (or not, depending on local preferences).

      • Richard Mlynarik

        Other than that, you need stairs/elevators, as short and simple and numerous as possible.

        Wide banked stairs+elevators. No narrow single-direction elevators, as US moron “architects” provide.
        Also transfers go and down under the trains and back up, far shorter and quicker because humans are less tall than tracks+trains+overhead.

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