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Friday, March 31, 2006

In the dark


So, about 8pm last night the lights blinked and the lamp in the corner blew out with a bright flash and a loud snap! After that we were all sitting there in the dark. The power was off up and down the road. Ellie was understandably upset.

After a while she started to get into the spirit of flashlights and candles. We read a pirate story by candlelight (The Ballad of the Pirate Queens) and listened to the radio for a while before we all went to bed. The power came back on about 2:30am.

When I got up this morning, three circuit breakers were blown. The X10 controller on the lamp that blew out was fried (it actually makes sound when you shake it) and one outlet didn't work. When I unplugged the outlet, the prongs were charred.

Luckily, everything else in the house seems to work (including the computers). I replaced the broken outlet this afternoon, so I think we're back in shape. I wasn't surprised about the X10 module. My experience with them is that lamp modules are pretty unreliable. All else the same, I would recommend appliance modules for that reason. I've blown something like 3/4 of my lamp modules in the last 2 years. Not one appliance module has failed.

Geeky math stuff


I use software in my calculus class, some proprietary (not my choice) and some free. One of the programs is an application called Octave. I wrote some improvements for it to support our chapter on vector fields, and this week my changes were incorporated back into the main project. It wasn't a big thing, only about 15 lines of program, but I was really pleased about it.

So naturally, I'm working up more improvements to contribute. It'll be great to have them all included. By the next time I teach Calc III, it's likely that all of the stuff we have to do by hand will just be part of the program. Very convenient.

Saturday, March 25, 2006

Ellie had a little lamb


We survived our evening with the lamb Spirit. It was about as challanging as you might expect. Spirit tends to eat anything within lamb reach. It's kind of like a toddler, except that the lamb can get around faster.

She was tired when we brought her home from school. I suppose she'd had a lot of play with the kids. So we watched a little Stargate on TV with her. She and Ellie sat on the floor.

After that, Ellie ran around with her for a while until I thought the lamb ought to get a break. We put her in the bathroom to calm down, and Ellie had to find other things to do with herself. The bathroom was also where Spirit slept overnight, after Ellie fed her her evening bottle.

I know you want pictures.

Ellie sitting with Spirit
Ellie feeding Spirit

Monday, March 20, 2006

We've got Spirit, yes we do!


Just went you quit reading the blog I actually have interesting news to report. I can't believe I did it. At Ellie's school, they have a newborn lamb named Spirit. It runs around in a diaper and the kids love it.

I signed it out for Thursday night. You can take it home.

Sunday, March 19, 2006

Pink as can be


It was spring break this week. Ellie went to visit her grandparents, and Linda volunteered me to repaint her bedroom. It is pink, a very pretty pink (although not as dark as she wanted). She got to see it finally today. For 3 minutes she was delighted, then she said I wanted dark pink. Too bad now.

Outings that make your feet hurt


You have to take advantage of the moments when Ellie is away. On Friday, Linda and I went to HyVee so she could try pushing a cart. We went down about 3 aisles I think, maybe 4. In any event, it was a good distance for her, probably a record.

We were slow, naturally. Very slow. Old people look fast near us. Still, the kind of distance we went can only be measured as a success.

Other things you do on break


We decided to do a bit of shopping downtown this week. We tried a few stores that people have been talking about for some time. Linda brought her wheelchair so we could go as far as we wanted and takes as much time as we wanted (without getting tired).

Downtown is not really for us, not Linda at least. There are huge cracks and broken pieces of concrete where the sidewalks meet the street. Some of the stores are so cramped you can't go through them without a wheelchair much less with one. Where there are ramps, they are the are too steep to navigate without help.

There was no bar in the bathroom of the used bookstore, so Linda needed me to help.

I know my friends are snobs about Wal-mart. They destroy small business, etc. But you can go into any Wal-mart in the country with your wheelchair and you'll be able to get around. It's flat and smooth and they will have at least attempted to make the bathroom accessible.

You can pretty much get the same guarantee at McDonald's. They even have baby-changing tables in the men's bathroom at most restaurants. That's cool.

The Pizza Hut in Bloomfield, IA on the other hand does not have accessibility bars in any of the bathroom stalls, the men's or the women's. This is despite a "Pizza hut supports people with disabilities" sticker on the front door. Yeah, whatever. I'll be eating at McDonald's next time.

Tuesday, March 14, 2006

A lesson in conditional probability



Probably the hardest notion you are likely to encounter in basic statistics class is conditional probability. It can be very counter-intuitive, and requires real care to get right.

It's easiest to understand by context. Consider that an AIDS test might be 97% accurate in the sense that it only generates false negatives 3% of the time. The same test might be 99.5% accurate because it only gives false positives 0.5% of the time.

If you, an ordinary person, with no special risk factors test positive, what is the probability you have the disease? Maybe you think 99.5% likely?

Not particularly likely it turns out. See, among people without any particular risk factors, AIDS is pretty rare. Of 1000 people who got tested, you might only expect 1 to actually be sick, but you'd get 5 false positives in a group that size.

So a single positive test really only means your probability of being sick is like 1 in 6. It's a lot less than you think, and it's not that easy to wrap your brain around. It's also the reason they retest people who test positive.

It's called conditional probability, because the question is about the probability of something being true based on information you already know (the condition). You are asking what is the probability of being sick, given the condition of a positive test.

Conditional luck



The reason for the statistics lesson is that Linda and I have been talking about conditional luck lately. People are always telling her that she is lucky.

Finally, I told her that she is conditionally lucky. Given that she had a very bad stroke, she has had a remarkably good and improbable amount of recovery. (In my way of thinking good*improbable=lucky.) That's what people see and what they can wrap their brains around.

It's not quite the same thing as being lucky. But it's better than being pure unlucky.

Saturday, March 04, 2006

A masked bandit


We had our first parent-teacher conference ever yesterday. We learned that Ellie is smart, but she would rather play than work. And she does things if she wants, and not necessarily if the teacher asks.

We got to look through her journal, where she writes a different letter of the alphabet each week and draws something that begins with that letter. Most weeks the teacher prompts with a few ideas that they might draw.

When we got to Z, I realized that what Ellie drew had come all from her. The teacher agreed; she had offered up zipper and zebra as possible things to draw.

Ellie drew Zorro.

Friday, March 03, 2006

Quote of the day


Riley has a yo-yo. It's not like this one. She has a fabulous yo-yo. It has a butterfly on it.

Thursday, March 02, 2006

Are you sneezing?


If you started sneezing about a week ago and it doesn't seem to be due to a cold, then you are allergic to tree pollen. Cedar and Juniper started pollenating. I am apparently allergic to these (no surprise, I'm allergic to almost all tree pollen).

It's nice to be not driving to Columbia all of the time to work on the autoambulator. It really made Thursdays a bit hectic. Linda did mention on Sunday that, as hard as it was, the autoambulator did seem to help.

We were at a restaurant where she had to do a lot of walking. She said that she is better at staying relaxed even when she walks fast (and is tired). That was what she had to be able to do on the treadmill, walk really fast but stay relaxed. Staying relaxed keeps her tone from getting really bad.

It was possibly the best walking I've seen her do there.

Awe, darn



Ellie is expanding her sentence structures lately. Whenever something goes slightly wrong, she is wont to comment, Awe, shit. She does it so often, that she is obviously doing it just to show off.

I've encouraged her not to say it, without trying to make a big deal about it. She would pick up on that and do it more, just to get attention. We seem to be getting past the novelty stage already because she says it less and less.

I explained that it isn't really that nice of a thing to say. What I really wanted to explain is, You really shouldn't say that. It just makes people think poorly of your father!