How long is a Dublin minute? Adventures in waiting around, with ‘real-time’ bus predictions

It definitely said five minutes. Passengers awaiting a bus in Dublin, 2010. Image: Getty.

It’s one of the little quirks of our postmodern wonderland that slight imperfections in a quasi-utopian service are complained about far more than the absence of the same thing: you’d rather no WiFi than slow WiFi, that kind of thing.

In a similar vein, until quite recently all the humble bus user had to go on when waiting on their chariot were timetables and some educated guesswork. How quaint it must have felt. In the last few years, though, the development of various breeds of real-time software means you can see your bus’s ETA down to the minute, via apps and on-street displays.

That’s the idea, anyway.

Dublin’s version of this, the Real Time Passenger Information system (RTPI), was launched in 2011, supplying travel information to a network responsible for 128m passenger journeys in 2016. And it has a bit of a reputation.

Every commuter has a story about buses supposedly coming closer before receding into the distance, or showing up on the displays, only to vanish entirely. “That thing’s been saying ‘6 minutes’ for a quarter hour now” sits alongside “shite weather, isn’t it?” in the annals of Irish small-talk. Different countries have their own version of the same popular discontent - some a little better, some a little worse.

Basically, RTPI works by inserting a GPS signal into a bus and working out how far it is from each subsequent stop along the route. Jeremy Ryan, head of public transport contracts with Ireland’s National Transport Authority, says that the system is fed with regularly-updated ‘profiles’ of how long a bus should take to get from stop to stop, with different profiles for different days and times. These profiles are aware of normal traffic and pre-planned roadworks, but can’t know about ad-hoc things like heavy rain or emergencies, which leaves the predictions a little sticky.

The NTA carries out quarterly surveys to assess the system’s accuracy. According to this research, about 97 per cent of Dublin buses arrive within three minutes of the scheduled time, which the NTA and Dublin Bus say is “well above industry norms”. Reassuringly for people convinced that their own area is cursed with malevolent software, there apparently aren’t significant variations between routes, directions, or times of day.

Approaching these assertions with the swivelled eye of healthy scepticism, I decided to engage in a bit of citizen’s quality assessment. I walked to some strategically-placed bus stops around central Dublin, waited for a bus’s expected arrival time to tick over to “5 minutes”, and measured how long it took to roll up beside me.

Not having all day, I limited myself to clusters in Phibsboro and Rathmines, 2-3km north and south of the city centre respectively, and to the city centre itself from O’Connell Street to South Great George’s Street.

And what do we find? Well, probably unsurprisingly, on the whole the RTPI system does indeed appear to be remarkably accurate. Averaged across 62 buses, the average time it took for one to arrive after the ticker moved to “5 minutes” was a lean 5:58. Bearing in mind that nowhere is it claimed that “5 minutes” should be taken to mean 5:00 exactly, keeping the average error down to less than 20 per cent is not too shabby a performance.

This makes all kinds of sense. A system with much more of an inbuilt error would be nigh-pointless to continue using from a passenger’s perspective. And it’s easy to see how a system with even a 3 per cent error would develop a negative reputation, considering how many people it stands to annoy every time there’s a slip-up.


That said, at different points of my experiment, “5 minutes” could have meant either 2:32 or 11:21. If you arrived at a stop proclaiming “5 minutes” on a given day last week, it seems there was about a 1 in 4 chance of the bus being more than 2 minutes early or late. Insofar as there was any variation between areas, buses heading into the city centre from the south side averaged 6:41, though there were hardly enough trials here to be statistically significant.

In sum however, we’d probably be advised to give the software some credit. For all I know, it may well have a conception of time divorced entirely from our idea of reality – but for the most part, when RTPI tells you your bus is 5 minutes away, it’s not exactly lying to you.

 
 
 
 

Here are eight thoughts on TfL’s proposed cuts to London’s bus network

A number 12 bus crosses Westminster Bridge. Image: Getty.

In 2016, the urbanism blog City Observatory had a modest proposal for how American cities could sort out their transport systems: “Londonize”.

Its theory, the name of which referenced another popular urbanism blog, Copenhagenize, was that the key plank of Transport for London’s success was something that even transport nerds did not consider very sexy: its buses.

Though the Tube might get more glamorous press, London’s bus service really is impressively massive: It carries roughly 2.3bn passengers per year—much more than the Tube (1.3bn), close to the New York City subway (2.8bn), and nearly half as much as every bus service in America combined (5.1bn), while serving a population roughly 1/35 as large.

How has TfL done this? By making its bus network high frequency, reliable, relatively easy to understand and comprehensive. We rarely talk about this, because the tube map is far more fun – but the reason it’s so difficult to fall off the transport network in Greater London is because you’re never that far from a bus.

Given all that, we should probably talk about TfL’s plans to rethink – and in most cases, cut – as many as 36 different central London bus services over the next few months.

I’m not going to rehash details of the changes on which TfL is consulting from next month: there are just too many of them, and anyway it’s someone else’s scoop. The story was originally broken by Darryl Chamberlain over on 853 London; there’s also some fascinating analysis on Diamond Geezer’s blog. You should read both of those stories, though preferably not before you’ve finished reading this one.

Before offering my own analysis of the proposed changes, though, I should offer a few examples. More than a dozen routes are facing a trim: the 59 from King’s Cross back to Euston, the 113 from Oxford Circle to Marble Arch, the 171 from Holborn all the way down to Elephant & Castle and so on. A couple – the 10, the 48, the C2, and at most times the special routemaster version of the 15 – are being withdrawn altogether.

On, and one new route is planned – the 311, from Fulham Broadway to Oxford Circus. This will help plug some of the cuts to the 11, 19 and 22.

So, what does all this mean? Some thoughts:

1) This might not quite be as awful as it initially sounds

TfL says that demand for buses has fallen by around 10 per cent in London in recent years. It predicts it’ll fall further when Crossrail opens, as passengers switch to the new line, or to the tube routes relieved by the new line. So: the idea of taking some unwanted capacity out of the system is not, in itself, terrible.

Striping out unnecessary buses should also improve air quality in some of London’s worst pollution hot spots, and improve traffic flow, hopefully speeding up journeys on those buses that remain. 

A map from the presentation in which TfL explained its plans, showing the reduction in bus numbers on key arteries. Hilariously, notes Darryl Chamberlain, “It no longer produces its own maps, so has had to use one prepared by a bus enthusiast”.

The plans might even free up buses and staff to increase frequencies in outer London where demand hasn’t fallen – though these plans won’t be unveiled until next year and, for reasons I’ll come to below, I’ll believe it when we see it.

2) For many bus users, a lot of these changes will pass almost unnoticed

By my count, I use nine of the affected routes with any regularity – but only three of the changes are things that I’m likely to be at all inconvenienced by. Most of the changes either affect a part of the route I don’t take, or one where there are easy, and pain free, alternatives.

This is anecdotal, obviously – perhaps I’m just lucky. But my suspicion is that a lot of these changes will go unnoticed by most passengers. It’s only the sheer number of them happening at once that makes this look like a big deal.

3) The Hopper fare makes this easier...

Once upon a time, if you had to switch buses, you had to pay a second fare. This isn’t true of journeys on the tube or railways – and since bus passengers have, on average, less money than tube passengers, it amounted to a pretty unfair tax on poorer Londoners.

But in January, in what is probably his most notable policy achievement of his two years in office so far, London’s mayor Sadiq Khan changed the rules. Now you can take as many buses as you want within an hour, for a single fare: that means you can switch buses without paying a penalty.

That will have made it easier for TfL to cut routes back: replacing a direct bus journey with one that requires a change no longer means imposing a financial penalty on passengers.


4) ...but not that easy

That’s about where the good news stops, though – because there are reasons other than cost why people prefer direct bus routes. Needing to change buses will be difficult for anyone with any form of mobility impairment, for example. Even for those of us lucky enough not to fall into that category, it’ll be annoying: it’s just easier to stay in one seat for 40 minutes than to get turfed off and have to fight for a new one halfway through.

More than that, from the passengers’ point of view, excess capacity feels quite good a lot of the time: it means your bus may well be nice and empty. Reducing the number of buses along those key corridors will also make those that remain more crowded.

5) The motive is almost certainly financial

Another of Sadiq Khan’s big policy promises was to freeze fares. He made this promise at a time when central government is massively reducing the financial support it gives TfL (the work, Chamberlain notes, of Evening Standard editor George Osborne, back when he was chancellor). And the Hopper fare, while a great idea in many ways, means a further reduction in income.

So: TfL is scrambling for cash: this is why I remain cynical about those new outer London bus routes. I would be amazed if money wasn’t a motivation here, not least because...

6) TfL thinks no one will notice

Any attempt to reduce tube frequencies, let alone close a station, would result in uproar. Hashtag campaigners! Angry people pointing at things in local newspapers! Damning reports on the front of the Evening Standard from the bloke who made it happen!

Buses, though? Their routes change, slightly, all the time. And do you really notice whether your local route comes every 10 minutes or every 12? That’s not to mention the fact that bus passengers, as previously noted, tend to be poorer – and so, less vocal – than tube passengers.

So cuts, and the savings they bring, are much easier to sneak through. TfL probably would have gotten away with it, too, if it hadn’t been for those meddling bloggers.

Although...

7) Scrapping the C2 might be a mistake

The C2 runs from Parliament Hill, through Kentish Town and Camden to Oxford Circus. In other words, it links north London, where a lot of journalists live, to the offices of the BBC and Buzzfeed.

As occasional New Statesman writer James Ball notes, this is probably not the easiest route to quietly shelve.

8) None of this is set in stone

The consultation doesn’t even begin until next month and then will run for six weeks – so all these plans may yet be forgotten. We shall see.

Anyway – here’s Darryl Chamberlain’s original scoop, and here’s some detailed analysis on Diamond Geezer. Please support your local bloggers by reading them.

Jonn Elledge is the editor of CityMetric. He is on Twitter as @jonnelledge and on Facebook as JonnElledgeWrites.

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