math

Ah, I'm so happy to be home tonight. After a really long talk with Magali last night, which was not extremely fun (can someone take over with this whip? I've been self-flagellating since last night and my arms are cramping up), I didn't sleep so well and had class from 8am to 4:45pm with only 15 minutes in between to walk to another building. By the end of the day I was so ready to go home and sleep, but then I ran into that cute French girl I mentioned earlier. Among other things, she's a math wiz, and as I tried to explain why this one transformation was so difficult, hoping she could help me, I realized that I'd made an extremely simple algebraic error and felt pretty stupid. See if you can do it:

b'=sum(x'(y'-ybar))/sum(x'(x'-xbar)) where xbar is the average of x over the entire sum. This somehow becomes

b'=sum((x'-xbar)(y'-ybar))/sum((x'-xbar)^2)

Hint: subtract xbar*sum(x'-xbar), which equals zero, I promise, from the first equation.

Can you believe I'm even thinking about this shit? Turns out the second equation (the result of the subtraction) has important implications for calculating something, but don't ask me what.

And this is for my class from 8-12:15 on Mondays. Needless to say I wasn't particularly perky.

After that I had a class about democracy in Turkey and Iran, but it was the first meeting so we didn't really do much. Fortunately it will normally take place Tuesday evening, so I won't have totally horrible Mondays.

What else ... I've only been reading Economist for two weeks and I'm already behind! My subscription hasn't started yet. Damn you myspace, I could be enjoying British humor!