The future price of electricity

I got my electricity bill last week, and I noticed a nifty new feature that's been added to it: a predicted electricity cost for the next year. And very interesting that prediction is, too.

Here is my annual expenditure on electricity for the last few years (the numbers are ridiculously low for several related reasons that I won't go into here):

2003: £45.36
2004: £33.14
2005: £38.26
2006: £51.04
2007: £55.71
2008: £48.74
2009: £48.30
2010: £56.16

The graph shows a noisy but nevertheless upward trend, consistent with inflation more than with any increased usage on my part.

What do you think my electricity company's prediction for my 2011 bill is? A prediction that I am assured is based on "actual readings", according to my account. £60? Maybe as much £70? No. It is £488.77.

So, what does npower know about short term electricity price inflation that I don't?

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The price of pears

I bought a bag of conference pears (lovely and crunchy) at Tesco last night, for £1. As I opened them today, I thought, "£1, that's quite cheap, how much is that per pear?" I counted them, and there were eight.

Without conscious decision, the calculation flashed through my head as follows: "Eight for a pound; that's half a crown each", then a slight pause before the next step: "so that's 12-and-a-half pence each."

Half a crown? What's that, I hear you youngsters say. Well, back in the dim and distant past, we didn't have this new-fangled dumbed-down decimal currency. We had proper pounds, shillings and pence. 12 pence to the shilling, 20 shillings to the pound; 12 times tables; the lot. How long in the past? Well, we went decimal on 15 February 1971. (I remember the excitement of getting shiny "new pence" in my change on the bus to school.) That's 40 years ago to the day.

40 years: oh dear, and I still think in old money! (Not all the time, I hasten to add. It's just that "eight half crowns to the pound" was so well drummed in that it's still the natural association. Then there's always 6/8d.) But, to the day: wow.

Never mind that. What about half a crown for a single pear! Outrageous! (OTOH, 12.5p is really cheap...)

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Computer Science meets King's Cross

I haven't been to London for a while, but I was there last week to give a talk. As I got off my train at King's Cross, I thought I heard an announcement: "The train currently standing at platform zero is the...". What? Platform 0? I listened to check I wasn't hallucinating, and there it was again: "Platform zero for the ..."

Now, I know King's Cross quite well, I thought. It has eight platforms on the main concourse, and also platforms 9 to 11 hidden away in their own private little siding. (Forget finding platform 9-and-3/4s: I've know people fail to find the real but well-hidden platform nine!) But platform 0? Srsly? Only computer scientists start counting from 0!

So when I got onto the main concourse, I checked, and sure enough, there were signs to platform 0. When I got back in Google-range, I consulted that fount of all knowledge, wikipedia. Yes, there is now a platform 0, as part of the refurbishment scheme. On the one hand, it seems a shame they've gone with platform 0, since that means platform 9-and-3/4 is still a "mistake" (there are tracks, not platform, between 9 and 10). But on the other hand: platform 0. Cool.

So I was disappointed to discover that once the refurbishment is completed, the platforms will be renumbered, starting from the much more unimaginative 1. (Presumably resulting in hilarity for all concerned as the zombified commuters, with the current numbering scheme hardwired in their cortexes, start making off-by-one errors, and end up scattered all over the country.)

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BoxCar 2D

BoxCar 2D is a neat little evolutionary algorithm, that over time evolves dune buggies (inside a physics engine) that have to traverse an ever more rugged landscape.

The little plateaus in the maximum fitness achievement give a lot of information about the environment. Will it ever get over that nasty spike at 396? Yes! But then there's that steep hill at 420... It finally powered over that at generation 39. But how long until it passes that gully around 490? At generation 54, it hauls itself out, and gets as far as the next bad obstacle at 529. Even after 700 generations, it can't get past that one... (Okay, I've been running this for too long, I admit. It's quite hypnotic. And it's fun watching later generations just power over obstacles that were literally insurmountable by their ancestors.)

What this shows is a combination of the power of evolution, and the restriction of a fixed representation. The algorithm can get so far, but to get further, there needs to be more novelty available. Look at the graph of average fitness. It rapidly shoots up to several 100 (here, fitness = distance travelled), but then it's just a noisy constant, with no overall improvement. Looking at the vehicles produced, it's easy to see why. They rapidly find good solutions within the constraints of a rigid octagonal body with wheels fixed to the vertices, but can then go no further. Watching the cars race across the terrain, it's clear they need more, maybe a flexible body, maybe something else. But they're locked into the one representation: that needs to change, to develop, too. I look forward to something like BoxCar 2D but with added evo-devo!

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roflysst

Watched the DVD of Bill Bailey's Dandelion Mind show last night. Brilliant, as usual. There was a great Internet abbreviation song, including the marvelous punchline roflysst (Rolling On Floor Laughing Yet Somehow Still Typing).

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spotting the placebo

A lovely letter in New Scientist (22 Jan 2001, p26):

From Phillip Gething

As part of my training to join a medical research ethics committee, I attended lectures on drug trials. We were told of a trial in which a patient spotted when her drugs had been switched, even though great efforts had been made to make the capsules appear identical. When asked by her GP why she thought the drugs had been changed, the patient replied, "I always put them down the loo. Until recently they always floated, now they always sink."

Fleet, Hampshire, UK

Being able to spot the placebo clearly wasn't the main problem here!

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lowercasing file names

(thanks to Ian Toyn)

find . -exec chmod u+w {} \;
for i in `find . ! -type d -name '*[A-Z]*' -print`
do
    oldname=`basename $i`
    newname=`echo $oldname | tr '[A-Z]' '[a-z]'`
    mv $i `dirname $i`/$newname
done
for i in `find . -type d -name '*[A-Z]*' -print`
do
    oldname=`basename $i`
    newname=`echo $oldname | tr '[A-Z]' '[a-z]'`
    mv $i `dirname $i`/$newname
done

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