固有値分解する

n <- 100
X <- matrix(rnorm(n*2),ncol=2)
Y <- X %*% c(1,2) + rnorm(n,0,0.01)
library(rgl)

plot3d(X[,1],X[,2],Y)

lm(Y ~ X-1)

XY <- cbind(X,Y)
M <- t(XY) %*% XY

eigenout <- eigen(M)

eigenout[[2]]

eigenout[[2]][,3]/(-eigenout[[2]][3,3])