On Wed, 23 Feb 2005, Stevie D wrote:

Tom Anderson wrote:

Morden (Z4) to Balham (Z3): 1.30
Morden (Z4) to Highgate (Z3): 2.80

I instinctively count a Z4-Z1-Z3 ticket as the same as a Z4-Z1 ticket,
rather than a Z4-Z3 ticket, but I realise I didn't make this very clear.

Fair enough.

You make it sound as though there is some great conspiracy afoot
whereby all those passengers going from zone 6 through zone 1 and out
the other side are getting a free ride and that you personally are
paying for every one of them.

Er, that's exactly what's happening. The problem we have at the moment
is this:

Morden (Z4) to Waterloo (Z1): 2.80
Morden (Z4) to Highgate (Z3): 2.80

That's not the same thing. Is there a conspiracy afoot? No.

Did i mention a conspiracy? Why do you keep telling me there isn't one?
Very suspicious if you ask me!

Are you personally paying for every passenger to travel that extra
distance? No. Do some passengers get a better "per mile" fare? Yes. So
what?

You can't say yes to one of those and no to the other! If some people are
getting more for their money, that means i'm getting less, which means i
am personally paying for them. Now, in practice, i suspect that the
subsidy is vanishingly small: there are a lot of people going into Z1,
very few people going out the other side, and the additional cost of
carrying them is modest. Nonetheless, i'm not objecting to the practical
result, i'm objecting to the principle of the thing; with the current
theoretical loophole, sooner or later, there's going to be a practical
problem - perhaps when hojillions of commuters from are travelling from
the west to Canary Wharf or Stratford City.

The simple correction is to count zones which are crossed twice twice.
For example, if a single in Z1 costs 2.00, and a single from Z1 to Z4
(or Z4 to Z1) costs 2.80, then the cost of extending a journey from Z1
to Z4 must be 80p; that would make a Z4-Z1-Z4 journey cost 3.60.

It sounds easy when you say it like that, but how easy would it be for
the passengers who use the tube in practice?

No harder than it is now: if you want a single, you hit the button on a
ticket machine and give it the money it asks for. The further you go, the
more you pay, with outer zones costing less than inner ones. There are
more combinations of zones to be priced, but i don't think that matters:
it's not as if users of the system memorise the entire fare table, they
just use the heuristics i describe above.

How much would a Z4-Z1-Z3 ticket cost?

3.60.

Yes, this is the same as Z4-Z1-Z4, but that's because a Z1-Z3 ticket costs
the same as a Z1-Z4 (now *that* is barmy ticket pricing).

You would very soon find that either most tickets for cross-London
travel were cheaper than Travelcards or,

ITYM more expensive.

if TC prices rose commensurately, that TCs become ridiculously expensive
and no-one would buy them.

True. That's why i go into the half-travelcard below.

I have no idea how you'd implement this for travelcards, though; you'd
want someone who lived in Morden to be able to buy a travelcard which
let them go as far as London Bridge for less than one which let them
go as far as Highgate,

Why? A TC gives you unlimited travel within the zones specified.

At present, yes. However, if you accept the idea that Zn-Z1-Zn is not the
same as Zn-Z1 for singles, it's natural to extend the idea to travelcards.
Intuitively, i think the travelcard i use to commute to work, a Zn-Z1
journey, should cost less than a travelcard which let me go all the way
across London when i felt like it. However, as we both observed, this is
very tough to implement.

It is very simple - there are three zonal variants (Z1-2, Z1-4 and Z1-6
[1]).

Was there supposed to be a footnote attatched to that?

but you can't just say it's for Z1-4 on the Morden side - what happens
if they get on the District Line? You'd have to get the customer to
specify which half of each line they wanted when they bought the
ticket, which would be rather silly!

Exactly. It gets almost humorously complicated very quickly. A TC should
give unlimited travel within the given radius. Making it any more
complex than this greatly reduces the utility of the TC.

Making it substantially more complex does. Making it very slightly more
complex might not. For example, honeycomb zones might work.

The only solution i can see is to split the outer zones into sectors,
and make travelcards specific to some combination of sectors, but that
way madness lies. Do away with travelcards, i say!

The honeycomb model. While this could work OK for individual fares, it
would be an absolute nightmare for TCs or other passes. Would you have
to specify everyone cell/zone your journey might pass through?

Exactly the same as now: the ticket would have to cover every zone your
journey actually does pass through.

What about situations where you could take a cross-London route or an
orbital route?

What about them?

What about people who buy TCs because they don't know where they will go
at the start of the day and want the convenience and freedom that a TC
offers?

Exactly the same as in three days' time: you don't buy a travelcard, you
use pre-pay, and the system caps you to the appropriate travelcard price.

TCs are great. What they offer is a simple, easy to understand, instant
to buy way for people to travel around London making full use of the
different modes of transport available. Anything to replace them that is
tube-specific penalises those in south London, anything that is
rail-specific penalises those in north London.

Those are both utter strawmen, and you know it.

Anything that is complicated penalises the occasional traveller, the
foreign tourist, the transport companies, the ticket seller, and every
poor sod in the queue

Meanwhile, the TC just penalises people who want to commute to and from
work, because it forces them to buy a ticket which gives them far more
than they need.

I'm actually, and very tentatively, in favour of scrapping travelcards
altogether. Prepay all round! Better yet, postpay - i travel, then i get a
bill at the end of the month, perhaps along with my council tax (if i live
in London, anyway). You'd actually have to support both, since they fit
different needs - just like pre-pay and contract arrangements for mobile
phones. I think this has all the benefits of TCs - i just get on the tube
and ride; i do have to worry a bit about every trip i take costing me, but
i don't have to worry about whether it's worth buying a TC in the first
place. You might think this would be horrendously expensive, but with a
system like this, where all passengers are buying singles rather than
mostly using TCs, singles could be cheaper. You could have an analogue of
period TCs (which benefit passengers by being cheaper, operators by being
predictable, and the public by encouraging PT use) by giving discounts for
heavy users (eg 50 quid buys you 55 or 60 quid of credit on prepay, or if
you spend over 25 quid a month on postpay, you get 20% off everything over
that, or whatever).

behind the guy who is trying to work out what zones he needs to travel
from Croydon to Barking then round the Goblin to Richmond, tube to
London, back to Croydon, out on the tram, back on the bus...

I don't see that that's intrinsically any more complicated than the
present system: you have to look at the route, see what zones it goes
through (ignoring bus legs and handling Tramlink specially), and buy a
ticket that covers those zones. Any difference in complexity would come
from the number of zones: at present, we have six, but a honeycomb system
would probably need more. I don't know exactly how many; we could split
the current outer zones into four sectors each, for 21 zones, but i think
that's overkill. We could simplify things to three rings of four sectors,
plus zone 1, for 13 zones; we could even have two rings of four plus Z1,
for 9 zones. I don't think 9 zones would be that much harder to handle
than six. Perhaps three rings of three, plus Z1, for 10?

Well, i for one am looking forward to riding crossrail at midday and
having a carriage all to myself.

Crossrail is not redundant capacity. Crossrail is vital, and long
overdue. Likewise Thameslink 20000.

There are parts of the network that are overcrowded and running above
capacity throughout the day. We do need to provide additional capacity
on these sections. What we don't need to do is to provide enough
capacity for everybody to travel at 8am and 5.30pm, because this results
in very poor asset utilisation.

Agreed. Was anyone actually suggesting that this is what we should do?

Or, and i think this is most likely to be the truth, is this what the
Conspiracy is actually planning to do, and you're trying to cover it up?
I'm on to you, Mr D!

tom

--
And the future is certain, give us time to work it out