dat<-read.table("http://www.matsuka.info/data_folder/tdkPCA01.txt")
dat.pca<-princomp(dat)
summary(dat.pca)
biplot(dat.pca)
dat.pca$loadings[,1]
scoreP1S1 = dat.pca$loadings[1,1]*(dat[1,1]-mean(dat$writing))+
  dat.pca$loadings[2,1]*(dat[1,2]-mean(dat$thesis))+
  dat.pca$loadings[3,1]*(dat[1,3]-mean(dat$interview)) 


dat<-read.csv("http://www.matsuka.info/data_folder/tdkCFA.csv")
dat.pca<-princomp(dat)

dat<-read.csv("http://peach.l.chiba-u.ac.jp/course_folder/AMSA_track_mens.csv",row.names=1)
plot(dat,pch=20)
dat.pca<-princomp(dat)
screeplot(dat.pca,type="lines")

dist = c(100,200,400,800,1500,5000,10000,42195)
log.dist=log(dist)

plot(log.dist, dat.pca$loadings[,1],pch=20,col='red',
   cex=2,ylab="PC loadings (1st)",xlab="Log(distance)")
plot(log.dist, dat.pca$loadings[,2],pch=20,col='red',
   cex=5,ylab="PC loadings (2nd)",xlab="Log(distance)")