Thursday, February 21, 2008

This is an animation I've produced this week to help illustrate a couple of concepts from Operations Research (a branch of ... let's say mathematics). I don't know as I write this whether the image will be shown as an animation. If not, you can probably just download it and open it in Quicktime or whatever. That might be preferable, anyway, since you're supposed to be able to slide the line back & forth with the slider & see what happens. I should compress the image for the web, I know, but I don't know how, sorry.

Loosely, the red lines show the contours of some objective you're trying to achieve, e.g., profit. So the various points on the graph represent various business strategies, and the further northeast you get, the more money you're making. But you can't go into the yellow regions, because of various constraints; each of those lines represents a constraint, probably due to your having a fixed quantity of some resource.

The animation changes one of the constraints, to show how the amount available of that resource affects the profit you can achieve.

Maybe I'd better leave it at that for now!

Sunday, February 17, 2008

With the right attitude, you can't fail

This story's about 8 or 9 weeks old now. I went with my family to Aotearoa for 6 weeks over xmasny, and this is the story of our taxi ride to the airport, at the start of our holiday.

The taxi driver was a cheerful, friendly fellow with a heavy Eastern European accent. Right at the outset, he asked us if we'd mind stopping at a petrol (= gas) station on the way. We had left in plenty of time, and the fare was fixed in advance, so of course we said fine.

He asked a few questions and told us a bit about his life, & at first it was pleasant. However, it's a long way to the airport from our place, & as the conversation wore on, the driver latched onto my 15yo stepson in a fairly misguided and very irritating way. He began to exhort him to work hard at school. That doesn't sound so bad, of course, but it was the way he went about it: "My sons, when they went to university, they never have girlfriends. You know why? They too busy, study, study, study. Now, one is an accountant, the other is a manager. Now, they have fifty girlfriends. They have nice car, nice clothes, they go into a nightclub, any girl there will want to talk to them. I talk to you now like a father, I give you good advice, you listen, you study hard, when you're twenty-five, you'll have very nice car, you can really enjoy life." And on and on and on.

Now, I know, attitudes to material success vary greatly. To my stepson, I'm sure, that sounded like a nightmarish future. But he's a very polite young man, and managed---only just---to feign interest. Eventually we got to the petrol station, & it was quite a relief, because the driver went inside, and concubine and I were able to commiserate with stepson and give him the strength needed to withstand the remainder of the onslaught.

Anyhow, until we got to the petrol station, we were assuming, as probably are you, dear reader, that our object there was to buy petrol. Evidently not. The driver went inside for three or four minutes, came out, resumed driving, got on his cellphone & had a quick conversation with someone about the errand. The only thing I really made out was the line, "He wouldn't sign it. No. I don't know. He wouldn't sign it."

The driver then advised us that there was some accident or roadworks or something on the usual route, & that it would probably be a lot quicker to go another way. I don't know Sydney's roads very well, & we weren't in a hurry anyway, so we said fine, whatever. So we took the alternative route, and it turned out to be very slow, with very heavy traffic. Our punctual arrival at the airport was never in jeopardy, which is just as well; otherwise, I might not have been so amused by the logical dubiosity of the driver's repeatedly indicating all the traffic and saying, self-congratulatorily, "See? I'm not the only smart!!"