## Slides 3-6
heart <- read.delim("../../data/heart.txt")
X <- cbind(as.matrix(heart[,!is.element(names(heart),c("chd","famhist"))]),famhist=as.numeric(heart$famhist))
P <- prcomp(X,scale=TRUE)
P
summary(P)
plot(P)

## Slide 9
fit <- glm(chd~P$x,data=heart,family=binomial)
summary(fit)

## Use of predict
fit <- glm(heart$chd~.,data=as.data.frame(P$x),family=binomial)
summary(fit)

XX <- X[1:5,]
nd <- as.data.frame(predict(P,XX))
predict(fit,nd)

## Slide 15
P <- prcomp(~sbp+ldl+adiposity+obesity,data=heart,scale=TRUE)
fit1 <- glm(chd~age+typea+famhist+tobacco+alcohol+P$x[,1],data=heart,family=binomial)
fit2 <- glm(chd~age+typea+famhist+tobacco+alcohol+sbp+ldl+adiposity+obesity,data=heart,family=binomial)
summary(fit1)
summary(fit2)