Secret Santa: A geeky Christmas Challenge Advent is nearly upon us, so it must be time to work out the mathematics of secret santa. I've been thinking about a mathematical problem, and I wondered if any of the assembled audience out there wanted to solve it. There may be a small bottle of gin for the person that does it.
The problem is to find an algorithm to find a secret santa assignment such that everyone knows who to buy a present for, but does not know who's buying the present. We also want a secure way of doing this, such that players cant tamper with the assignment. I do not know the answer to this, and it may be possible to prove it's impossible.
Dear Santa, For christmas this year, I would mostly like pie. Any kind of pie would be nice. I realise I have not been good all year, but I have been mostly good, and deserver more pie. Except mince pies. You have too many of them around Christmas, and they generally no longer contain meat.
If you cannot bring pies down the chimney, and I understand the EU regulations are strong on this point, then any of the other things would be very nice.
- Anything from my Amazon wishlist. (I'd be perfectly happy with the second hand stuff, o rindeed buying it through somewhere not on Amazon!) - A nice fountain pen. I mostly like Parker pens, as it saves me having to write my name on it, and tend to like ones which the nibs don't break on. I believe the vintage ones are better quality. - A pie. Did I mention pie? - A lump of coal. - A subscription to private eye. - Nice writing paper or notebooks. I always look at it in stations, and think, gosh, this is nice, but expensive, but it's a nice gift. - Interesting beers, wine or gin always welcome. I particularly like interesting bitters, a good drop of claret, or Tanqueray 10, and Hendricks. - Don't forget the pie.
A surreal day Obama has apparrently won the nobel peace prize. ( This is nice for him, but they also gave it to Kissinger.)
On the same day as this, Obama has ordered NASA to go to war on the moon. (He really doesn't like cheese)
One of the professors here is having his 70th birthday. The college have put up signs to Professor Preeces'(sic) birthday. The distinguished academic is now running round the college with a bottle of tippex and a marker pen, correcting the apostrophe.
How do you get to Carnegie Hall? I actually got Lou to ask me this in New York; it is a pun I thought it was never possible to make in a real life situation, and I laughed for minutes.
Lou and I are currently tired and in the US; we spent four nights in New York, and I must say I still don't like it. To me, New York is like London, but quieter, ruder, busier, less sophisticated; it's fun to wonder around the landmarks, and there were some amazing bits. Greenwich Village was vibrant and exciting, the view from the top of the Empire State building (cliched) is spectacular, and it's a very exciting place to be. The quantity of food and the Delis are amazing, and I like getting served pickles but to be honest it ain't a patch on London.
For example, a ticket to a Broadway show costs $100 _at half price_; at least three times the amount in London. The noise is incredible at all times, with people using the horn on their cars more often than the breaks. Nobody seems to like each other, or have any time, and in London at least they're polite about it. It kind of feels like a mediaeval city in the sense that everyones crowded together, it's dirty, smelly, falling apart, and people are always trying to sell you something or get money from you.
We've arrived on the west coast today, after a 4am start- poor little Lou is having an afternoon nap. Already, it's nicer; air is cleaner, people are friendly and actually want to stop and chat and help out. They seem to have a clue and be actively trying to be environmentally friendly. We have a Prius, which is very exciting as it has more buttons than Cadburys.
We're staying here in San Francisco for a few days, before heading down the west coast, and then a couple of days in Las Vegas and the Grand Canyon. I can report that the quality of tea is much better than on trips passim, but I still miss many things about England! Save me some summertime...
Ballooning in the Namibian Desert So I left my intrepid reader in Africa, no doubt pausing with baited breath as to what was hapenning next. Would I be eaten by tigers? Aparrently no, not least because there are no tigers in Africa. Here's a rather detailed account of our dessert trip in Namibia.
So we set off for the desert; we had hired a car, packed sandwiches, gin, and everything else we needed for a journey. We cunningly followed the guide books suggestion of what routes were passable with a decent car, not necessarily a 4x4; this is important, as even a reasonable hire car costs 30 pounds a day, but a 4x4 is at least 100.
The Namibian roads leave a lot to be desired being made of gravel, and strewn with rocks. It's pretty impossible to do more than 50mph on them, and even that's not easy, and some of the roads are just impassable without aformentioned 4x4. You know the sort of road that you drive up on the way to a national trust house which is quite exciting because you know it's not very long and has a cream tea at the end of it? It's like that, for hundres of miles, and not a cucumber sandwich for ready money.
Anyway, we gamely tried, only to be defeated about an hour away from our destination by a big rock hitting the undercarriage and killing the on board computer. This road, editors of the Brandt guide take note, was not suitable for anything short of a juggernaut, and probably most suitable to be avoided completely.
We were in the middle of nowhere; not just somewhere on a B road in the Cotswolds, but really nowhere. Maybe a couple of cars a day would pass. No mobile phone of course, but fortunately some buildings on the horizon; Cath and I hiked up there for a couple of miles, just as it got dark, and fortunately it turned out to be some very nice people, who offerred to drive us the hour to where we were meant to go. It could have been a lot worse in the end, but we got to where we were going only a few hours late.
Now, we were staying on the outside of a massive great national park near Soussovlei the deal is this, that you get up at the crack of dawn and get taken to a big balloon set up in the middle of nowhere. You get in the basket, and after a little while the sun comes up over the desert, which is pretty special, and you see all the animals running around, and the birds, and it's all incredibly peaceful. Well worth the fortune it costs! ( if you're planning a trip, you could do worse than look at www.balloon-safaris.com ) When all this is over, you land (in the sense that you hit the ground and hopefully don't fall out while some small black children try and keep the thing upright) and get taken to a champagne (cava) breakfast round the cornet. Which is very pleasant in the middle of the desert. You attempt to climb sand dunes, realising that you are too fat to be bothered halfway up.
It's a very interesting place all in all- my first real time in a desert and there's suprisingly much and interesting wildlife. The place we stayed at was a great campsite, you're given a tree, and you camp under it. There's a very reasonable dinner buffet where they had barbecued meat, including Oryx, wildebeast, Impala (my personal favourite), springbok, and, er, chicken I think.
After a couple of days there, we set off home. Cath and her mum took an air taxi, having to catch a flight and not wanting the breaking down on a rubbish road in the dessert experience again. On the way home we stopped at a plce called Solitaire, which is so quaint and remote they use it to film Westerns in, and it serves apple pie, and only apple pie, of superlative quality. We avenged the karma gods by giving a ridiculous amount of water to a family broken down in the desert (they were quite suprised that we had so much, but grateful nevertheless). We stopped at Wimpy with the campest man in Africa(surreal, but the only place to stop). We eventually made it back to Windhoek, ruining our second hire-car on the way. Cruddy roads. Interesting country.
Ben is in Africa! What a terribly exciting place! It's very big, and I've hardly been to any of it yet. You might think it's a long way down the road to the chemist, but that's nothing compared to the bigness of Africa. Listen,...
My location is Windhoek, Namibia to be precise, and I have so far eaten:
Zebra Crocodile Oryx (twice) Chicken
Which are all TASTY. Apart from the crocodile, which tastes a little bit like a chewy old fish. But it did come quite quickly (was a snappy meal). Hehehe, I'm here all week.
Local transport consists of various strange man in various cars which have seen better days (mostly 1980), although Top Gear would love it... it's like a trip back through motoring past. The way it seems to work is that you pop your Panama hat on, and walk around. Within 0.6 milliseconds a dodgy man will take you to where you want to go in exchange for some large sounding amount of money that varies, but seems to be about three quid. The idea of a meter seems to be anathema. Occassionally, I'm told, if you're lucky you get a mugging thrown in.
Alll the houses in town are gated with security guards, dogs, barbed wire, and I even noticed a dead snake as a warning to potential criminals; I don't know what the crime rate is like, but there's certainly anecdotal evidence that it's high. It's depressing rather than scary. It reminds me of the quotation from "Cry the beloved country":
"Cry, the beloved country, for the unborn child that is the inheritor of our fear. Let him not love the earth too deeply. Let him not laugh too gladly when the water runs through his fingers, nor stand too silent when the setting sun makes red the veld with fire. Let him not be too moved when the birds of his land are singing, nor give too much of his heart to a mountain or a valley. For fear will rob him of all if he gives too much."
Tomorrow we go out into the country for some hot air ballooning and a night in the desert!
Left wing continuation I saw Tony Benn speak tonight. I think he's one of the finest public speakers of our time, and I admire his principles.
( It was, unfortunately, a meeting about Gaza, which in general had a lot of the student left wing brigade talking about nothing much in particular. I don't think anyone agrees with what happened in Gaza, and I think it was a strange session of preeching to the converted. )
George Galloway, scheduled to speak, couldn't be bothered. It's no great loss.
A lot of free-range chicken is fed with soya that comes from deforested areas of the Amazon. We've helped Peter, our Devon-based free-range chicken farmer, develop a special feed, rich in British ingredients, which is free from rainforest-destroying soya. Visit our free-range chicken section for more details.
There was a statistician post advertised for (the research agency that works for) the MOD. The aim of the job was to research ways to prevent and detect Chemical/Biological attacks on British troops (statistically quite an interesting problem!)
I was of the opinion that doing this job would be morally more justifiable than working in the city; my friend was of the opposite opinion, as she pointed out that any research could be turned around and used from an offensive point of view as well.
After learning that lemons have risen from 19p to 28p during the last year (Telegraph front page, June 11th), gin drinkers with a bitter taste in their mouth will be sweetened up to know that limes are still available for 19p in my local supermarket.
Whilst this might act as a Tonic to readers Browned off with the economy, with 55p on a bottle of spirits in this year's budget, it could be the be-gin-ning of the end for those of us trying to keep our Spirits up.
Maths question I have a maths question- anyone out there that knows anything much appreciated as it's stumping me?
I have a general stochastic matrix P representing a MC- so the sum of all the row elements add up to one. The simplest form is :
( 1-p p) ( r 1-r)
I need to find a form P^n which I think one way to do in general is to diagonalise P=D^{-1}AD.
Is there a simple way to do this for general stochastic P, or is it obvious that it's impossible? You can show trivially that 1 is an eigenvalue.
I can do it for the simple 2x2 matrix above; if it's not possible to do in the general case, is it possible for simpler matrices. My matrix I'm interested next is
1-p p 0 0 0 ... r 1-p-r p 0 0 ... 0 r 1-p-r p 0 ... ...
... 0 r 1-r
Hope that makes sense, any pointers appreciated- my linear algebra is really rusty!
In pursuit of a decent cup of tea I'm in the USA for a conference, which is quite exciting; also very strange, two countries separated by a common language and all of that. On landing at the aeroport, the first thing I see on the television was Tony Blair; the second thing was David Beckham. Both of these people seem to be enormously popular, so I conclude that the US is ten years behind Britain.
I'm staying in a small town called Annapolis, which is really very nice. Maryland is incredibly green and leafy, and it seems that the entire state is either a big forest or bits of a big forest that have been hacked down to build pretty suburban houses, or more often, larege out of town shopping malls. They have, and the reasons still escape me, drive through automatic teller machines. Drive through pharmacies. Despite this obvious need to do things quickly, everything seems very laid back. People keep telling me how historic this place is, and they apparrently signed the Treaty of Paris here which ended all that trouble in the colonies with the tea and whatnot and set up the United states.
The conference itself is quite dull; I'm a statistician looking at networks on a conference about internet measuring. Some of it is interesting, most of it is dull, and instead of having multiple track conferences ( lots of talks going on at the same time) you have one long session for everyone. So If you're not intersted in the topic, you sit at the back of the room and use the WiFI...
I wend to see the Baltimore Orioles (Go O's!) on Monday; Russ and Rachel happenned to be in town, and we continued our association with drinking beer at sporting events, now internationally. It's actually a lot better in person than on the television- the stadium is fantastic and has many fried food and beer, lots of room, and a good atmosphere; I think I still prefer cricket and rugby, but baseball definitely well above average.
My quest for a decent cup of tea outside England continues. They have lipton here, the scourge of all tea drinkers abroad, and do the normal thing of brewing tea with hot, not boiling water. Despite my attempts to educate the world, the message still is yet to get through. You also have a choice of milk, which is either "Half and half" or 2%. I do not know what either of these are, but it does not help with the tea quality.
In my room, there is a machine where you put water in the top, a little packet marked "tea" in the front'; you place your cup ( Paper, not china!) in front of the machine and it spits out a substance which is almost, but not quite, entirely undrinkable. Oh dear. I am Arthur Dent.
... Wetherspoons lackey: Is everything alright for you? Me: Well, actually, I could do with a spot more gravy (waving gravy boat hopefully). Wetherspoons lackey: You must order him at the bar Me: All I want is a little bit more gravy- I'm afraid you gave me next to none. Wetherspoons lackey: I cannot help, you must order him at the bar. Is everything alright for you? Me: No, everything is not alright, I need more gravy... <Wetherspoons lackey walks away to tick next customer service book, rudely ignoring customer anguish...>
Her Majesty and Her Majesty's Parliament Today was one of my favourite days of the year, The State Opeining of Parliament. I love living in a country where Her Majesty's Gentleman Usher of the Black Rod, whilst wearing some very fetching black stockings, has the door ceremonially slammed in his face to reassert an insult paid to King Charles 1 in 1642, when the speaker Lenthall reasserted the right to the Commons independence by saying "May it please your Majesty, I have neither eyes to see nor tongue to speak in this place but as the House is pleased to direct me, whose servant I am here." Yes, the occasion is silly, but the point is well made.
However, looking at what Parliament has actually done in the last year is very disappointing, and this years programme similarly uninspiring. See: http://www.opsi.gov.uk/acts/acts2007a.htm
All of these acts seem to be vapid- nothing of any merit in many of them. Quite a few of the bills (the Planning Gain Supplement (Preparations) Act, The Special Court of Sierra Leone (Act), are procedural and are only a couple of paragraphs long. Yes, they are important, but it can't have taken much of Parliament's time.
There are the standard finance acts that must be passed- the middle management of the countries finances. However, there is nothing, not one act, which I think does anything substantial to improve life in the country or do anything to address many of the problems in the world! Even the ones that set out to, for example The Mental Health Act, were sufficiently watered down so as not to have as much bite as they could have done.
Perhaps we were distracted by Mr Blair's prolonged exit, his successor's honeymoon period, or perhaps parliament needs to reassert it's power over a lacklustre government programme, remember speaker Lenthall's impertinence, and actually spend some time getting something useful done.
Five percent update! It's been a while since I updated on the five percent project- I start with 500 pounds, I make five percent a week by betting, and I get one million pounds in three years time.
Well, there is bad news- I should currently have £942.82, but I only have £608.21. However, the good news is I have got to 608.21- a 21% return in less than 3 months, pretty sly for a white guy.
James and Penny's wedding After VOLES, and a few hundred more miles driving, we turned up in Ledbury to James and Penny's wedding. From before we woke up, it rained and it rained and it rained- the way there was a little wet, driving through some fairly large puddles and we were quite lucky to get there. Many of the guests were late, but the bride managed to get there well over an hour late. She was lucky to get there- a 4x4 had to be commandeered, and very nearly a tractor.
As the wedding went on, it became very clear that we were being rained in with some of the worst rain England has ever seen- we could get to the church and the village hall for the reception, but anywhere out of the village was impassable by anything short of a tractor- and only then just. The food and the reception went on, and it was a very lovely wedding. I think often people spend too much time and money focusing on the showy aspects of the wedding without realising that the most important thing is company, lots of food, and a free bar. Nobody remembers the gold sparkly glitter in the shape of pineapples on every table, or the silver embossed place mats.
After the speeches, in which the groom told us that spending his wedding night with 50 of his friends was not quite as he envisioned, the local farmer helped evacuate those that wanted to to a local hostelry- the rest of us decided to brave it out in the village hall. As lots of people had left, there was copious booze, and it put me in mind of what it must have been like in the air raid shelters in the blitz. We danced on and drank on, and eventually people went to sleep in the back room. I'm never very good at sleeping somewhere odd, managed about an hour and a half. When it got light, I went to investigate and found a friendly DHL driver who showed us the way out.
It was a scene of devastation outside- cars abandoned, very few roads passable, but we did make it back to the guest house, and then I went back to resuce the others, and buy harry potter, which I still haven't had time to read! All in all it was a fantastic wedding, a little bit strange and passed in a bit of a blur, but we'll certainly be remembering that one in years to come.
VOLES! VOLES was one of the best weeks I've been on in a long time- campsite was pretty perfect, and weather very nice indeed for camping. Not sunny, as then your tent gets too hot in the morning, not too wet, except at night when it didn't matter, it was in the middle of the New forest with several million unfeasibly large twigs to burn, and a good few hundred yards from the nearest other campers. Most importantly the company was lovely- I was a little bit worried that there would be a lot of young'uns, but actually it was mostly older people. I say older- I'm still the oldest- but people what I knew anyway!
The New Forest is a wonderful part of the world, I've never been here before and as well as being an easy drive from London is incredibly pretty and feels fairly isolated. And has wild horses, donkeys, and cows. There's lots of interesting things to do, and was a really nice relaxing time. Just what I needed after submitting my very boring paper.
We did a load of fun things- the otter sanctuary contained lots of long things, which kept gill happy, a cider farm, where we bought extraordinarily cheap cider, a nice local pub where we ate a couple of times, and a big meadowy area where the most ridiculous wide game was played on the final night, involving lots of torches and capturing the flag. In the evenings, there were many silly campfire conversations and much gin: The psychiatrist's game, defining the voles SI units, and much general silliness.
Oh, and we did a revue as well! The old people were lovely, and gave us tea and cake.
More Political Geekery As another political aside, The Rt Hon Tony Blair is the first ex-prime mister to be appointed Warden or Deputy Warden of the CHiltern Hundreds since 1937.
As far as I know, it is the only time that the Prime Minster and First Lord of the Treasury, had not been a leader of his political party since 1940, when Churchill replaced Chamberlain.
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