Human Transit

the need for maps of your freedom

Posted on November 19, 2012 in Access, Maps, Mobility, Modeling

Remember this map?

I used it in the earliest days of this blog, and it's in almost every presentation I do. It's from a tool that allows you to select a location in a city and see blobs (technically isochrones) showing the area you can get to in a fixed amount of time using transit plus walking. This one is for 9:00 am and the three shades of blue represent travel times of 15, 30, or 45 minutes. In essence, the software takes the point you select and runs the equivalent of Google Transit trip planning searches to find a points where the travel time crosses the threshold; these become the boundaries of the blobs. (For details behind this crude summary, see Aaron Antrim's comment on this post.)

I call this a map of your freedom. It's useful for two potentially transformative purposes:

Helping people and organizations understand the transit consequences of where they choose to locate, and thus to take more responsbility for those consequences. This, over time, can help people who value good transit to locate where transit access is good — something that's very hard to discern from a typical bus map but that becomes very obvious here. You can even assess access to specific things that you value, based on exactly where the blobs are.
Helping people visualise the benefit of transit — access to your city — as a freedom, and thus to understand more clearly what transit does for them. It broadens the narrow notion of travel time – which is often understood for only one typical trip — into a picture of your possibilities as a transit rider. The percentage of a city's resources (jobs, housing, retail etc) that is in the blobs for a particular location could also form the basis for a meaningful Transit Score that could replace the technologically biased scores now used by WalkScore.com.

The original tool is a beta buried deep in WalkScore's archives. It's basic and very, very slow.

The other main alternative is mapnificent.net, by Stefan Wehrmeyer. Available for many cities, Mapnificent.net looks good …

… except that it contains two fatal assumptions:

Initial wait time is excluded.
Some timing of transfers is assumed, based on the author's experiences in Europe. So he uses an average transfer wait time of 1/3 of the headway instead of 1/2 of the headway, which would be appropriate for random transfers.

Here's the problem. Both assumptions mean that Mapnificent's assumptions undervalue frequency and overvalue vehicle speed. Since this conceptual bias is already very, very common (see Chapter 3 of my book), Mapnificent is seriously misleading in a way that can be really unhelpful. For cities that I know, especially area with lower frequency service, Mapnificent wildly overstates the convenience of transit, and fails to show how locating on frequent service will get you better access to the city.

In my network design course we talk about this. When figuring travel times in the course, I insist on using 1/2 of the headway as the intial wait time and the same as the transfer time (unless there's a pulse) so that frequencies weigh heavily into true travel times, as they do in life. This sometimes sounds silly: If a route runs once an hour does that really mean I wait an average of 30 minutes? Or do I just build my life around the schedule? I view the two as the same thing, really. We're not describing literal waiting so much as time when you're in the wrong place. We're describing the difference between when you need to arrive and when you can actually arrive. This could take the form of arriving at work 29 minutes earlier than your shift starts — consistently, every day. Effectively, you end up waiting at your destination.

So there are a range of judgment calls to be made in designing these things, but it's worth getting it right because the potential utility of this tool is so significant. The good news: I'm involved with people who are working on something better. Stay tuned!

the same “empty buses” fallacy, over and over

Posted on November 15, 2012 in General

This morning, Andrew Sullivan, whom I usually find intellectually engaging, featured a confused article about transit productivity from Eric Morris on the Freakonomics blog. It's the old line about how because buses are often empty, they're not a very efficient transit mode. I first rebutted it three years ago and the rebuttal hasn't changed at all.

I quickly wrote the letter below. But the big announcement is after the letter!

Eric Morris on the Freakonomics blog has fallen into the familiar trap …
To put my remarks in context: I’ve been a transit network design consultant for 20 years, and am also the author of the blog HumanTransit.org and the book Human Transit (Island Press, 2011) which rebuts many of the false assumptions in this article.
Morris's argument rests on the false assumption is that transit agencies are all trying to maximize ridership as their overriding objective.
In 20 years as a transit network design consultant working across North America, Australia, and New Zealand, I’ve never encountered a transit agency that pursues a ridership goal as its overriding purpose. Transit agencies are always required to provide large amounts of service despite predictably low ridership, for reasons including basic access for seniors and the disabled and the perception that service should be delivered “equitably.” While equitable is a slippery word that means different things to different people, its effect is to justify service spread all over an urban region, even into areas where ridership is inevitably low (usually due to a combination of low density and street networks that discourage walking).
In my own work, I refer to these predictably low-ridership servics as coverage services because they are tied to a coverage goal that conflicts with a goal of maximum ridership. Typically the coverage goal is stated in the form “__% of residents and jobs shall be within ___ feet (or meters) of transit.” This goal requires service to be spread out over areas where prospects for ridership are poor. I then encourage transit agency boards (or Ministers) to think consciously about what how their service resources should be divided between ridership goals and coverage goals.
If this method ever becomes common, it will be possible assess bus services that are trying to achieve high ridership. Only that universe of services is relevant to discussions about whether bus services provide ridership effectively.
A more extensive geometry-based discussion of exactly this issue, and how it needs to be managed in policy thinking is in Chapter 10 of my book Human Transit.
Regards …

The big announcement: I'm not going to do this much anymore. Here is my response, but hey, regular readers, any of you could have written this, right? After all, the rebuttal has been on this site for three years! Could everyone please bookmark that, or bookmark this, and just send a link whenever you see this same argument? Would save us all much time. Thanks!

transit as a city’s bloodstream: the video

Posted on November 11, 2012 in Connections, Transfers, Meditations, Simulation, Vancouver

Watch this video, and maybe you'll grasp the beauty of a great transit network, a beauty that has nothing to do with the technology it runs, but everything to do with the real life of a city and the feedom of its people. Public transit vehicles moving around Greater Vancouver, an entire day compressed into 2.5 minutes.

The original is here. It's by STLTransit, who has done a number of other cities.

Long ago I posted another of these, for Auckland, New Zealand. It uses endearing tadpoles instead of white dots. It's also interesting because Auckland's is not a single unified network, as Vancouver's is, (although we're working on it!). You can see the difference if you watch closely, using the tips below.

So many people see public transit only as a vehicle on the street, or a thing they're waiting for. But when you watch this video of a well-designed unified transit network, you can see that it's a gigantic interconnected organism. And like all organisms, it's made up of complex but rhythmic motion.

Like your heart and lungs, the network effect of transit is quiet, ignorable, and yet the foundation of everything. The network is one being, moving to a beat. It's made of connections, little sparks of energy that you must imagine whenever two dots touch, as the dots hand off to one another like relay runners. For example, as you watch the video, watch this spot, especially toward the middle of the day:

That's Phibbs Exchange, an example of strong pulse scheduling. At a langorous pace (representing a pulse every half hour or even every hour) you'll see many white dots gather themselves into a single bright dot, shine brightly for a moment, then "pulse" outward again. What's happening is that many buses that run infrequently are converging on a point and sitting together briefly, so that people can transfer from any bus to any other.

I'm not sure I'll ever convey to my non-transit friends that regardless of what you think of buses, a pulse is a beautiful thing to watch. Phibbs is more spread out than I like, and I photographed it at a quiet time of day, but in an ideal one, like the ones in downtown Eugene, you see this gradual gathering of energy to a climax, then a release. Gradually the buses arrive, until finally they're all there. You see signs on the buses announcing different parts of the city, all the places you could go right now, from here. The drivers get off the bus briefly, chat with customers, point them to the right service. People meet by chance. It happens many times a day and yet there's always this sense of event: here, at this moment, you have service to all these different places, ready to go right now. Enjoy the banquet of choices, select your bus, and let's go. In a moment it's over, the buses all gone, the place quiet or even deserted, like a field after a storm has passed. And in half an hour or an hour it will happen again.

And it's not a random thing, like a storm, but part of a huge intentional network that (in Vancouver's case) is designed. This pulse is one of the network's many continuous, reliable heartbeats. It's one big organism, made of unconscious rhythmic motion and circulation as all organisms are. It's inseparable from the life of the city it serves. And you're part of it.

on cities, conservatives, and getting past the boredom

Posted on November 7, 2012 in Meditations

The Atlantic's Sommer Mathis argues that a major party cannot win again in the US without competing in the cities. Vindicated New York Times statistician Nate Silver (@fivethirtyeight) puts it even more baldly in a tweet: "If a place has sidewalks, it votes Democratic. Otherwise, it votes Republican."

And that's a problem.

Only in the US has the conservative party so totally abandoned the cities. In the UK, Canada, Australia and New Zealand, conservative parties compete for inner city seats and sometimes win there. That's because these national parties understand the need for cities to function and that this requires a government role.

Conservative parties in those countries are also careful about managing elements of their base that thrive on the demonization and exclusion of some kind of demographic Other, such as racial, religous, or sexual categories. Messages that disparage these groups are now so unacceptable in major cities that they cut off voters who might otherwise support a conservative message. The daily experience of city life is all about sharing small spaces with people who are different from you, and prospering from creativity that arises from that mixture of perspectives and experiences, so demonizing diversity amounts to demonizing the very idea of the city.

All this is very related to public transit, this blog's core concern. I've argued in the Atlantic that transit thrives on thinking that embraces diversity instead of presuming fixed divides. To me, that embrace of diversity must include the richness of views, passions and human experience that are currently trapped and concealed inside the word "conservative."

Conservatives can help make good transit policy, once they are engaged in conversation about it. Conservative-dominated places like Alberta and Utah have made remarkably aggressive transit investments, justifed in part on sensible bipartisan understanding of what cities are, and what they need to thrive as engines of prosperity and innovation. When I've worked with elected boards or officials on difficult choices facing public transit in a city, I've noticed that self-identified conservatives are as least as likely as self-identified liberals to lead on the hard choices, by which I mean angering a core constituency or risking public complaint in order to meet some urgent large goal such as balancing the budget or establishing a clear policy.

The conservative-liberal or Republican-Democrat divide, as the media has constructed it, is not a real story. Delusional narratives are supposed to be entertaining, but this one is both delusional and boring. We will leave this story behind only when we start pointing out how searingly boring it is. The media are desperate to entertain, so only that message will get through to them.

Here is the real story: There is a polarization-vs-consensus divide, with large forces arrayed on the side of those who are terrified that people might begin listening to each other. There is an information-vs-ignorance divide, with large forces arrayed on the side of stopping the flow of information and rational argument.

Cities are places where, over time, the power of listening and information is most likely to prevail. They're not the only places; thanks to the internet, you can stay informed and immersed in conversation even if you're surrounded by 100 acres of sheep. But cities make the process involuntary; it happens to everyone to some degree. You cannot walk down the street (here's where sidewalks matter!) without encountering diversity and seeing how essential it is to city life. You cannot help meeting people of different races, religions, and sexual identities. That's what a city is. It's why polarizers and will always hate cities, and why tyrants will always find them hard to control. But it's also why they are such engines of growth and creativity in a world where information is power.

happy “secular sacred day”

Posted on November 6, 2012 in General

Still jetlagged from four absurdly busy weeks working in Australia and New Zealand, getting back just in time to vote in Oregon today.

As I've said on Twitter several times, eligible US voters who do not vote today have no right to complain about anything on my blog in the future. Declining to vote is a rejection of your democratic rights and an expression of consent toward those who would prefer a more oppressive state. It is also an expression of contempt toward those who have made sacrifices to protect democratic rights.

In short, I agree with Andrew Sullivan that this is a "secular sacred day."

I'm not telling you who or what to vote for, of course, nor telling you how I voted.

For a helpful rundown of US state and local ballot measures that will affect public transit mobility, see here, a the Overhead Wire. The Transport Politic looks like it's also setting up to cover transportation issues being voted on nationwide.

More soon.

new york: instant bus rapid transit

Posted on November 5, 2012 in Bus Rapid Transit, New York City

If you ever wondered how fast you could really create a Bus Rapid Transit line, well, New York City has done it just in the last couple of days:

Could use embellishment, but everything you need for speed and reliability looks like it's there.

This happens to be a replacement service for an out-of-service subway line. For more, see here.

new york subways after hurricane sandy, etc

Posted on November 1, 2012 in New York City

I am way off the grid near Kerikeri, New Zealand for the weekend.

So here's a map of the NYC subway system today, after the hurricane:

http://www.mta.info/sites/default/files/pdf/SubwayRecoveryMap.pdf

Bravo to Larry Gould of MTA who I'm sure was involved in figuring this out, though I doubt it was as much of a challenge as his work on September 12, 2001.

Have a good weekend. If you're a US citizen and you don't vote by Tuesday, I forbid you to ever complain on this blog about anything, for the rest of your life. So there.

dublin: “spaghetti with rainbow sauce”

Posted on October 25, 2012 in Urban Structure

Aris Venetekidis tried to draw a diagram of all the infrequent, overlapping, marginally useful transit services in Dublin:

Eric Jaffe has the story. Venetikidis uses mapping to discover chaotic network design, and propose simplifications. My work, too, often begins with drawing a network map for a transit agency client, helping them see their service in a different way.

quotes of the week: cars vs buses in delhi

Posted on October 25, 2012 in Bus Rapid Transit, Developing World

"Car owners are the creators of wealth. Do you realise that they get exhausted sitting in their cars due to traffic jams and they reach office completely tired? It affects their efficiency. Do you want them to perform less?"

— B B Sharan, the chief petitioner opposing Delhi's
new on-street Bus Rapid Transit system, on
the grounds that it leaves less space for car traffic.

"The problem of car users, who are in a minority, is being portrayed in the press as the people's problem. The fact is that less than 10% people in Delhi use private cars. More than 33% travel by buses and 30% walk to work."

— Geetam Tiwari, a road safety expert and professor
at Delhi's Indian Institute of Technology (IIT)

After months of drama, Mr. Sharan's complaint is being considered by Delhi's High Court.

Note that even the professor is reluctant to note the obvious: that buses that are allowed to run quickly and reliably will be more useful, and thus likely to attract even more than 33% of travelers. Unless, of course, you assume that class boundaries are absolutely rigid, with eternally fixed numbers of "bus-people", and that nobody changes their behavior based on utility. With that assumption, you're stuck with a purely entitlement-based argument, still a very strong argument in Delhi but not the only one.

Side note: Summing up the professor's percentages, it appears that some significant share of Delhi commuters are much-besieged cyclists, riding in immensely dangerous conditions. The daily reality of the Delhi curbface is that vendors fill up pedestrian spaces, including any sidewalks/footpaths, forcing pedestrians as well as cyclists into traffic lanes. Traffic in Delhi is often slow but always turbulent, with vehicles accelerating unpredictably to jump into perceived gaps in traffic.

First photo: BBC

how auditors get transit wrong: a lesson from vancouver

Posted on October 23, 2012 in Education, Vancouver

Elected officials love to demand "audits." Auditing means that you hire high-prestige people who will scrutinize the books of an agency with particular genius, and deliver recommendations that resound with authority.

But many of the companies hired to audit transit agencies don't seem to understand transit. That's certainly the evidence of a recently commissioned audit of Vancouver's TransLink, which discovered $41 million in potential annual savings including $5.3 million from cutting low-ridership services. (Extensive detail and media reaction is gathered here.)

Like many audits, this one just assumes that low ridership means "without justfication."

But low-ridership services are unjustifiable only if ridership is their purpose.

If you haven't read my book, or read this blog much, you may be under the impression that the goal of all public transit is high ridership, and that low-ridership services are therefore failing, evidence of waste, and should be cut. In reality, every transit agency runs service that has a purpose other than ridership. These services, which I call "coverage" services in my own work, have purposes such as:

Equitably distributing service to all areas that contribute tax revenue to the agency.
Meeting the urgent needs of small numbers of people living in areas that are expensive to serve (seniors, disabled, isolated rural pockets of poverty etc)
Satisfying a coverage standard, which is a statement of the form "___% of the population live within ___ metres/feet of service". The specific purpose of these statements, which most agencies have, is to determine when service must be operated despite predictably low ridership.

The TransLink audit appears to be simply ignorant about the universal tension between ridership goals and coverage goals. They recommend cutting coverage services because they have (predictably) low ridership. This is exactly as logical as throwing away your microwave because it doesn't produce ice.

When an auditor' assumes that ridership or fare revenue is the only goal of transit, they are expressing a certain set of values. This is a valid philosophical position, but it is not the only justifiable one, nor the only one that is widely held in most urban populations. So auditors do citizens a great disservice when they present their values as the only possible ones. In 20 years I have never encountered a public transit agency that actually deploys service exclusively for ridership. Now and then and auditor swoops down and criticizes the agency for the low-ridership services, often implying that the agency didn't already know about them.

Transit agencies need the backbone to reply to these audits firmly, explaining that low-ridership services may exist for purposes other than ridership, such as those listed above, and that if these services reflect the voters' values, they are as legitimate as any other.

Transit agencies can also support clearer auditing processes if they identify which of their services are intended mainly for coverage, which means their low-ridership should never be counted as evidence of failure. I have worked with several agencies on forming clear statements about the percentage of resources that the agency wishes to devote to coverage service. Once those services are documented, everyone can stop complaining about the low ridership of those services, because high ridership is not their purpose.

Auditing is one of those high-prestige professions, like architecture, that is prone to form echo-chambers that resist the introduction of outside information and perspectives. Great auditors, like great architects, are suspicious of their own echo-chamber and always looking for perspectives from outside of it. If you want to be a good auditor of public transit agencies, read my book! It will help you avoid the TransLink auditor's mistake, and many others.

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