dat <- read.csv("http://www.matsuka.info/data_folder/hwsk8-17-6.csv")
dat.lm<-lm(ani~otouto, dat)

plot(hatvalues(dat.lm))
dat.lm$residuals
x = dat$otouto
mean.x = mean(x)

h = 1/length(x)+(x-mean.x)^2/sum((x - mean.x)^2)
hatvalues(dat.lm)

e.std = e/(slm$sigma*sqrt(1-h))
rstandard(dat.lm)

(e^2*h)/(2*slm$sigma^2*(1-h)^2)
cooks.distance(dat.lm)


dat<-read.csv("http://www.matsuka.info/data_folder/tdkReg02.csv")
plot(dat)
dat.lm<-lm(sales~., data=dat) 
install.packages("DAAG")
library(DAAG)
vif(dat.lm)
lm.price<-lm(price~material+design+dump, data=dat)
p.rsq = summary(lm.price)$r.squared
vif.p = 1/(1-p.rsq) 
summary(dat.lm)

dat<-read.table("http://www.matsuka.info/data_folder/tdkPATH01.txt",header=TRUE)
plot(dat,pch=20,cex=2)
dat.lm1<-lm(absence~interest,dat)
dat.lm2<-lm(study~interest+knowledge,dat)
dat.lm3<-lm(grade~knowledge+study+absence,dat)