
How well do London buses match the timetables? - michjedi
http://www.michalpaszkiewicz.co.uk/blog/timetables/index.html?q=nhn
======
jnty
On trains and planes, my main critieria is that I arrive by the stated arrival
time and therefore am pretty unfussed by stories about padding time etc -
that's more of a long term structural concern than something that will bother
me on the day. I think operators have figured this is all most people really
care about over time (perhaps excepting highly competitive routes.)

You lose this ability to check timings with a non-fixed timings, and have to
rely on 'oh, it's probably about half an hour from here to here' or google's
guess at the real timetabled journey you'll do (which the operator hasn't
really promised you at any stage.) People don't seem to mind this too much.

I wonder if part of this is that waiting for a bus is usually less pleasant
than being on one in countries where there is often cold/windy/rainy weather.
That's something you don't really get with long-distance trains or planes. I'm
going to be grumpy if I have to wait in the pouring rain for 15 minutes, even
if I still make it to my appointment on time.

~~~
chrisseaton
Right - the arrival time is a no-later-than and that’s all I need. People
complain about leaving a gate in an aeroplane and then sitting on the apron
for a bit - who cares if you’re on the ground or in the air or even going
backwards - I just care about my arrival time and don’t mind what you do as
long as you hit that.

I use a flight that’s regularly delayed by half an hour but still gets there
half an hour early. Whatever - I make my connection every time.

~~~
bluGill
I also care about departure time. If I arrive with one minute to spare
(counting security and check in) but the plane leaves 2 minutes early I don't
get their on time through no fault of my own. If I'm even a second late I
accept it is my fault.

~~~
sokoloff
Airlines I've flown publish and abide the door-closing time. (For Delta
domestic flights, it's 15 minutes before scheduled departure, 30 for int'l. I
think they put 20 minutes on domestic boarding passes as a buffer against
watch skew arguments.)

I've seen the gate agents paying scrupulous attention to that, to ensure they
don't close the gate early if any pax who have checked in haven't boarded.

------
vidarh
TFL cares a great deal about these kind of contracts with users.

Years ago I was involved with a project to build dynamic displays to show bus
times (mostly for third parties like e.g hospitals that wanted to display bus
times as a service, but they're in use on some bus stations like Vauxhall and
East Croydon as well).

TFL did tons of testing to ensure we complied with requirements to ensure the
display would remove time estimates if it could not reach the API often
enough, etc. to ensure we never misled passengers.

They were very adamant that the displays always had to under-promise based on
what information was available.

------
velox_io
I've been in London for five years and don't think I've ever used the printed
timetables, the live ones at some bus stops work surprisingly well (and saves
me having to whip out my phone to check City Mapper, which started in London).

Something that the article missed is that late buses are compounded. As the
delay causes more people to wait, those people getting on delay the bus even
further, that's where the adage "wait ages for a bus, then two come at once"
stems from. Even if the bus behind it is also delayed, it makes up time as the
previous bus has scoped up all passengers. Occationally buses will divert/
terminate to rebalance the timetable.

I was recently in hospital, where the wifi wasn't great so I spent a lot of
time looking out the window, and onto a busy junction. During the later part
of rush hour buses often arrived together, even saw three of the same bus
arrived together (only a couple vehicles separating the last bus) at one
point! (like I said, bad wifi) It was staggering seeing so many ambulances
arrive during the weekend, they often arrive together as the first ambulance
clears a path (like in Die Hard 3).

You also see that on the tube, when people are fighting to get on a train
(delaying it further) then the one following a couple of minutes behind is
largely empty, it's even a little more pronounced as trains can't leapfrog
each other to spread the load.

------
SamBam
The conclusion of the article seems to be related to the general rule that if,
say, a box of nails advertises 1000 nails, the manufacturer will have set the
actual average to be higher than 1000 nails so that some large majority of
buyers will always have at least 1000 nails in the box. (I seem to recall an
A-Level stats question on my exam asking what the average should be, to ensure
that 95% of buyers received at least 1000 nails.)

Again the statement on the box is not a statement of reality, but a contract
that the buyer should be (almost) guaranteed of getting at least 1000 nails.

If I recall correctly, calorie values on nutrition boxes are the same, at
least in the US: a 100 calorie snack bag will have _at least_ 100 calories,
because the FDA mandates that the seller should be at minimum providing what
it claims.

~~~
NullPrefix
>If I recall correctly, calorie values on nutrition boxes are the same, at
least in the US: a 100 calorie snack bag will have at least 100 calories,
because the FDA mandates that the seller should be at minimum providing what
it claims.

Check out our new BigMac Zero. At least zero calories.

~~~
ben_w
You jest, but TicTacs are allowed to be labelled “sugar free” despite being
91.3% sugar because, to quote, “the amount of sugar per serving (1 mint) is
less than 0.5 grams, FDA labeling requirements permit the Nutrition Facts to
state that there are 0 grams of sugar per serving“ -
[https://www.tictacusa.com/en/faq](https://www.tictacusa.com/en/faq)

~~~
benj111
So Nutrition facts can round to the nearest gram despite allowing servings to
be less than a gram? What a well thought out policy.

Ps I thought the US used imperial measures, why are grams getting used?

~~~
bluGill
US is a mix of measures. Imperial is allowed, but there are only a few places
where it is required. Metric is in fact very common - but only for measures
not in day to day use (that is intentionally contradictory have fun figuring
it out)

~~~
benj111
In Europe theres regulations over labelling etc.

In the UK if you buy a 'pint' of milk it will still be labelled 0.568 litres.

Presumably there are some rules in the US also, or labels could just use some
obscure measures that hide what a product contains.

~~~
vinay427
Yes, there are definitely rules. Virtually every product on store shelves in
the US seems to be labeled with metric or imperial units depending on what is
more convenient or less obscure to the public, though sizes for many products
are the same across the oceans which can make for weird numbers for everyone.

Labeling definitely isn't always imperial in the US, and it isn't always
metric in many European countries. Regulations tend to do a good job of
avoiding units that are obscure in that they're rarely used for the specific
purpose in question or would have clumsy numbers like the pint to liters
conversion you noted.

e.g. A common PET bottle size in the US and elsewhere is 0.5L, which in the US
is labeled as "0.5L"/"500mL" usually along with the, in my opinion, somewhat
pointless "16.9 fl oz". Meanwhile, a 2L PET bottle is also common in the US
and is labeled (and known by virtually everyone) as "2L".

~~~
NullPrefix
>which in the US is labeled as "0.5L"/"500mL" usually along

I hope that you mean it's labeled as 0.5L or 500mL and not both of them with a
slash.

~~~
vinay427
Yes, exactly. I was hoping my quotes helped clarify that but I can see how
it's unclear...

------
YayamiOmate
I've noticed this when riding on a long tram lane which is supposed to be a
fast track and a transfer one. So I prefer more often trams, because it means
less people.

I've also noticed that I dont have to remember timetable because it's
basically organized in so-much-trams-per-hour, so it's 20mins or 15, 12 etc.
So I just need to remeber a minute-offset and an interval.

As a side effect, i've noticed that at rush hour when interval is 5 mins the
timetable stops to have meaning because tram can be within -1 to +3 of
timetable arrival, that means it can be virtullay any time. Also, I should
wait max abt 5 minutes.

I think that intervals vs arrival time change meaningfullness as a relation of
interval vs timetable confidence, and passenger travel time confidence for
that matter. If you can't plan your arrival at the stop better than +-1min you
don't need exact times for 5-6 minute intervals. For 60min it probably makes
sense. I guess one could derive good metrics for this.

~~~
bluGill
Generally being 5 minutes late for an appointment counts as you get a dirty
look but you are on time. Being more than that and they get mad. So 5 minutes
or less intervals mean someone running just a little late isn't actually late
to their appointment.

------
cosmodisk
It'd be interesting to see how train companies perform. They publish stats
based on destinations. I take train to work and so it happens that it also
goes to the airport. If the train is delayed more 10 min, they'd cancel
smaller stations and go right to the airport. I wonder how this gets reflected
on their stats of which I'm very skeptical to start with.

------
tialaramex
The buses and underground in central London do have real timetables by the
way, but they're primarily for the operators.

If you drive buses or trains you want to know when your service is supposed to
start and how long it's supposed to take to get where it's going. But for
passengers this is a metro service (except for the first and last services on
routes which shut overnight) so they don't care if this is an 1105 running two
minutes early or an 1100 running three minutes late.

~~~
TheOtherHobbes
TFL has a journey planner which assumes the timetables are correct.

[https://tfl.gov.uk/plan-a-journey/](https://tfl.gov.uk/plan-a-journey/)

Timetables are more or less irrelevant at peak times, but if you have
connections to make out of peak hours any delays can make a big difference to
your day.

------
vidanay
I have noticed this paradox when accessing my VPN time based code. More often
the time until refresh is >30 seconds than it is <30 seconds (60 seconds
between refreshes)

~~~
quenstionsasked
This doesn't hold. The timing of the VPN code widget is not a random variable,
but rather fixed. Thus, sampling a random inspection time of the widget has
equal probability of being in the 0-30s bucket as it does in the 30-60s
bucket.

For a bus, the intuitive explanation is that if you were viewing a timeline,
the biggest parts of the timeline would be the "late" buses, and thus you're
more likely to "inspect" (arrive at the bus stop) during one of these longer
stretches.

------
SiempreViernes
Wow, that certainly took a sharp turn into melodrama at the end.

What happened to truth is that there wasn't much clarity to begin with and
then the schedulers found out that they could meet expectations by using that
ambiguity. Mystery: solved!

Now lets see if they complain about current and electrons going in opposite
directions...

------
juskrey
Obviously the bus can't arrive before departure

------
imatworknow
I wonder whether this is the norm for other cities?

~~~
carlob
I live in Rome. Here we have a schedule for departures, and real time
tracking. The schedule for departures is a lie, meaning that any given
departure can be canceled without notice, so unless a bus has already left the
terminus you cannot be sure it ever will.

So I'm guessing our public transportation works worse than the one the author
describes in Rwanda.

~~~
michjedi
Interesting! How do you usually plan your journey in Rome, and how often does
your journey work out like the plan?

~~~
carlob
I walk out of my place, if I see a bus is approaching I might jump on it
otherwise I'll use the subway or a car sharing platform.

Consider that:

* I'm one of the few people in this city to be in walking distance from a subway station (blame it on archeology)

* Car sharing can be cost effective compared to public transportation: it costs 20-30 cents per minute, so if your trip is 10-15 minutes and you're traveling with another person the car is faster and cheaper.

* The only reason I consider the bus at all compared to the subway is because the stop is literally at my doorstep.

