Cwomen1 <- read.table("c:/temp/BFox.txt",header=F,skip=1)
names(Cwomen1)  <- c("year","participation","tfr","menWages","womenWages","debt","parttime") 

Cwomen1$tfr  <- Cwomen1$tfr*(Cwomen1$year != 1973) +1931*(Cwomen1$year == 1973)

Cwomen1.lm1 <- lm(participation ~ tfr +menWages +womenWages +debt +parttime +year, data=Cwomen1)

 # Use the vif function from the car package

library(car)

vif(Cwomen1.lm1)   


 # Conduct principal component analysis with the princomp function

Cwomen1.pca  <- princomp(Cwomen1[,c(1,3,4,5,6,7)], cor=TRUE) 

summary(Cwomen1.pca)

loadings(Cwomen1.pca)

plot(Cwomen1.pca,type="lines")