#データ読み込み
CHTG=read.csv("CHTG.csv")

#ロジスティック回帰分析
res1=glm(X~CH+TG,data=CHTG,family=binomial)
summary(res1)
res1$linear.predictors
plot(res1$linear.predictors,CHTG$X)
curve(exp(x)/(1+exp(x)),add=T)
abline(h=0.5,lty=2)
abline(v=0,lty=2)

#線形判別分析
library(MASS)
res2=lda(X~CH+TG,data=CHTG)
res2
names(res2)
c1=res2$means %*% res1$scaling
c1
C=apply(c1,2,mean)
C
plot(CHTG$CH, CHTG$TG, xlab="Cholesterol", ylab="Triglyceride", pch=c(as.character(CHTG$X)))
A=C/res2$scaling[2]
B=-res2$scaling[1]/res2$scaling[2]
abline(A,B)
res3=predict(res2)
names(res3)
res3$class
res3$x
plot(res2)

#Mahalanobis距離
dat1=CHTG[1:12,2:3]
dat0=CHTG[13:24,2:3]
m.dat1=colMeans(dat1)
m.dat0=colMeans(dat0)
v.dat1=var(dat1)
v.dat0=var(dat0)
mah0=mahalanobis(CHTG[,-1],m.dat0,v.dat0)
mah1=mahalanobis(CHTG[,-1],m.dat1,v.dat1)
mah1-mah0