Linear Regression and Matrices

So I know a good amount of math, more than the average guy on the street, but I love to learn new things. This week I passed out copies to the book Supercrunchers to my two kids in math club, and to get the ball started we went over how linear regression is calculated. I had no idea, and I found the following link that does a really great job, but it does almost the whole thing with matrices. I had never seen this before, and I was basically stunned. One nice thing about it is that it gives a good application of the matrix transpose. The fact the calculation of the linear regression numbers can be written as a fairly short matrix equations is shocking to me. This of course reminds me of determinants, which continue to amaze with their power and breadth of application.

Chat about work with physics teacher.

I never really understood work. The physics kind too. So I asked a fellow teacher to sit down with me an explain it. I recorded it with ISight, and now I have something to share with my students, and you...