Sunday, October 26, 2003

An unusual visitor

Last night while I was working at the computer I heard a noise at the window. Looking around, I saw a bird struggling to find a perch on the ledge of the office window. It didn't seem concerned about my presence so I moved closer to the window and saw it was a very small owl. I made a sqeeky noise with my lips and its head swivelled right around to look straight at me with its big yellow eyes. But it held its ground for maybe another minute as it surveyed the gravel car park and lawn in front of my studio, no doubt on the look out for food. It is welcome to all the rodents it can catch around here.

I am sure that this must be a Northern Saw-whet Owl from its small size. I checked out the structure of the vinyl window this morning and find it hard to believe that it found a foothold there.

This is my second encounter with a Saw-whet. The first was a few years ago at dusk when I was taking the dogs for a rather late walk. We were following a path I have hacked through the alders at the back of our house, and this owl was perched just above head height. Again I was surprised how tolerant it was of our presence, especially with four dogs running around. As we drew close it flew off down the path where it found another perch where it waited again until we got just that little bit too close.

Tuesday, October 21, 2003

Suffolk Punch DNA bank

According to this BBC report, there are only 18 stallions on the studbook for this magnificent breed of horse, which over the centuries has carried men into battle, pulled their ploughs and hauled their timber.

Now the Rare Breeds Survival Trust is raising money to preserve DNA from this and other rare breeds of British livestock, some of which are rarer than the Giant Panda.

Let me find you a filly for your proud stallion seed
to keep the old line going.
And we'll stand you abreast at the back of the wood
behind the young trees growing
To hide you from eyes that mock at your girth,
and your eighteen hands at the shoulder
And one day when the oil barons have all dripped dry
and the nights are seen to draw colder
They'll beg for your strength, your gentle power
your noble grace and your bearing
And you'll strain once again to the sound of the gulls
in the wake of the deep plough, sharing.

Read all the lyrics to Heavy Horses by Jethro Tull.

Monday, October 20, 2003

Wolf reintroduction

Maritime Noon today carried an interview with researcher Andre Whittaker who claims there is sufficient habitat to sustain small populations of wolves in Kejimikujiak and Highland national parks here in Nova Scotia. The Eastern Wolf is listed as a species of special concern with only 2000 individuals in Ontario and Quebec.

This webpage has some good information on wolf reintroduction. Studies show that they are not as big a threat to livestock as is often claimed by farmers. When they were reintroduced to an island, the moose population actually increased as the wolves removed less healthy animals, freeing up more habitat for healthy productive animals.

So, what's your view on wold reintroduction. Is it a good idea or not? Submit your views at my poll on this issue.

Thursday, October 16, 2003

The Monty Hall Problem

There can't be many novels that include much mathematics, but Mark Haddon's "The curious incident of the dog in the night" breaks the mold.

My first reaction to the Monty Hall Problem is that there are some errors in the way the problem is solved in the novel. First is shown a purely mathematical solution, which I felt was flawed because it seems to treat the action of the game show host as a probability, whereas in some cases it is a foregone conclusion which of the remaining doors he will open. Second is a graphical solution which looks convincing, but my feeling was that there are two options here which are identical, and that oversimplifies the problem.

I look at it this way. There are really two games that you could play, and that the concept of changing your selection is a red herring. The first game is when you have 3 doors to choose from, the second is when you have two doors to choose from. If you don't play the first game (or at least forget about it once the host has opened his door) and consider the second game a case of choosing between two doors, rather than deciding whether to change your original choice, I can't see how the odds are anything but even.

I think that the conflicts in this problem boil down to this. There is a difference at the last stage of the game between making a random choice and making a switch from a previous choice. So what are the probabilities that these options will result in the same outcome?

Keith M Ellis has written a really good discourse about this problem, along with references and links.

Wednesday, October 15, 2003

Son of Juan?

Just a few weeks after hurricane Juan passed by, we have another wind warning in effect for today. Gusts upto 90km/h expected this afternoon. Nova Scotia Power predict more power outages (they only just got everyone reconnected) due to trees that were partially damaged succumbing to the breeze. When are they going to figure out that underground distribution lines would be a good idea. Lets join the developed world.

We were fortunate in that we suffered no serious damage from Juan. It passed by a few miles to the west, and had been downgraded to a tropical storm by the time it reached us on the north shore. We lost a few shingles from the roof, but they probably should have been replaced a decade or two ago in any case. The worst was the lack of power for three days. It was warm, so heating the house was not an issue, unlike when the power goes out in winter. The biggest problem was water supply. We had filled the bath tub before the storm, so we could at least flush the toilet and have a cold wash. But that ran out on day 3 and I had to fill a 50 litre plastic tub from the beaver dam way back in the woods, and push it home in a wheel barrow. Fortunately some neighbours have a generator and were kind enough to let us have drinking water. So we got by, but I would much rather the power company improved their infrastructure.

Monday, October 13, 2003


My wife is busy today marking students' assignments. The subject is vector cross products and dot products. Someone in the class came up with some new maths, best described as vector division, which seems to involve lots of canceling out, but really simplifies the work.

What is really sad is that half the class has adopted this new math. Apparently its easy to spot the originator of this concept because her paper is full of crossing outs and scribble. All the others are neat duplicates of the original cutting-edge work.

Sad. Really sad. Fancy getting caught out like that.

So exactly what is a blog?

This whole blog thing is mind boggling. Maybe blog is an abbreviated anagram of boggling? This looks like a good place to find out more: Google Directory - Computers > Internet > On the Web > Weblogs

Why blog?

Look at this way. If a blonde pastic bimbo can have a weblog, then so should I. It looks like she stopped writing in June. No doubt run out of ideas? Can I do any better than this empty head?