8AM

I've never had trouble waking up early in my life before. In high school, waking up at 6:37 or so every day seemed like nothing. And I'd fall asleep at 11:30, sometimes as late as 12:30, with almost no problem every night.

What a luxury, man.

I teach 8:00 AM classes three days a week now, and they are killing me. I don't know why, I have literally no idea, but I haven't been able to fall asleep until after 2:00 AM by myself at the absolute earliest since I got those classes assigned to me. Some nights I took some fraction of a sleeping pill because I knew I was going to die in class if I didn't, but some nights I just try on my own, and sometimes I'm up until 3:00 or 4:00 on those nights struggling to fall asleep.

I got a pad for my bed, which didn't really seem to help. Making it colder so that I can use the big comforter does seem to help a little bit, but not really.

Normally I wouldn't really mind. I get to all of my classes on time, even if I feel a little dead. But I feel so exhausted afterward that sometimes I fall asleep, and that's gotten me in trouble twice so far. Once, I fell asleep at 4:00 PM or so and didn't wake up until 7:10 PM, which was ten minutes after I was supposed to be on duty at night study. That sucked. The other time, I just completely slept through a science meeting. I woke up at the tail end of it and rushed in just in time to talk to my boss about my classes' progress, but I still felt terribly stupid about it. I feel like it might have messed up other things, as well, but I can't remember them at the moment.

Sigh.

I know that a schedule change is coming up next week because some teachers have to go out to the sticks for a few weeks to teach some special program. I really, really hope that maybe I'll get moved from 8AMs because I just can't do it. But I'm also really afraid that - since some of the English teachers are leaving - I'll have to teach English again.

And god damn, do I hate teaching English.

Peace out.

Derangements

I gave my kids in my Canada class a problem today that was basically like this: A monkey is throwing a ball labelled 1, 2, 3 into boxes labelled 1, 2, 3 randomly. What is the probability that none of the balls go into the right box?

For something with such small numbers, it's easy to do by hand. One student was trying to figure out the rigorous way to do it and asked me what the answer was, so I just laid it out by hand and finished it in a minute or so. But then he said, "But what if it's a bigger number?" So I started to work on it with, say, 20 boxes.

So I started to work on it in class, but didn't solve it. I went to dinner and thought a little bit about it, but didn't really make much progress and got distracted by Chinese and also food. So I started to work on it when I came back to my apartment, and it turned out that it was much more difficult than I had anticipated for n greater than 5 or so.

It turns out that you need to use a concept called derangements, which is basically when you find all of the permutations where nothing has been mapped to its proper spot. As in, 1 doesn't go in the first position, 2 doesn't go in the second position, etc. There was a famous problem that was equivalent to "define derangements" from a long time ago called the hat problem (or umbrella problem) where n people go to a party, and you want to find how many ways (or the probability) they leave with all the wrong umbrellas.

I eventually figured out and understood whatever I needed to know about it. !n = (n-1) x (!(n-1) + !(n-2)). Basically, imagine that the first guy at a party picks a hat, call it hat #k. Now think about what guy #k does. If guy #k picks the hat #1, then what's left is !(n-2). Since there are (n-1) ways that guy #1 can pick a guy #k, this is (n-1) x !(n-2). Now imagine that guy #k doesn't pick hat #1. So there are (n-1) ways that guy #1 can pick hat #k, and then we still need to derange !(n-1), so that's (n-1) x !(n-1).

It took me way too long to understand that paragraph above. I think most of the reason why is because I misread the Wikipedia summary of the explanation. I actually went so far as to edit it with my own misunderstanding, and then edit it back when I realized I misunderstood it and why. But anyway, after that, I was able to understand pretty much whatever else there was about it, including the summation formula and another proof via the inclusion-exclusion principle, which I wish I had seen first, sigh.

I don't really know why I wrote this. It was a little bit nice to do math for like 4 hours tonight, but also a little bit dumb and I felt pretty miserable with myself for taking so long to understand some of the things I was doing and solve some of the problems I was working on. I need to do more problem solving and programming, but also more Chinese, and also more music and guitar and drawing, aye...

Peace out.

Proximity

As frustrating as it was sometimes to live in the orphanage in Cambodia, one thing that I didn't realize about it until just now was how effective it was at helping me to learn Khmer. The only other foreigner there with any regularity at all was Mike, and sometimes even he would just randomly disappear. So if I wanted to have any interaction, there was a very good chance that it had to be in Khmer. I mean, I lived with 70 kids or so, of which probably about 15 could speak reasonable English. So for 55 of the people I lived with, I had to learn Khmer to really communicate with them in any effective way.

Here, though, I live exclusively with foreigners. On my floor, there's one American guy who's married to a Chinese woman, but she speaks really good English and I don't think he speaks really any Chinese at all. And elsewhere in the building, it's the same - either only English speakers, or just people who speak really good English in general.

So there's no reason to speak Chinese here. In Cambodia, I needed it if I wanted to say or explain or listen anything at all with what was going on around me. Additionally, there was a lot more commotion because there were 70 kids running around. Here, I just live with a bunch of English speaking adults. We all sit in our apartments and stare at screens.

So I've done a poor job with the Chinese so far, and I'm pretty disappointed about that.

Peace out.