library(faraway) data(state) statedata <- data.frame(state.x77,row.names=state.abb) g <- lm(Life.Exp ~ ., data=statedata) summary(g) g <- update(g, . ~ . - Area) summary(g) g <- update(g, . ~ . - Illiteracy) summary(g) g <- update(g, . ~ . - Income) summary(g) g <- update(g, . ~ . - Population) summary(g) summary(lm(Life.Exp ~ Illiteracy+Murder+Frost, statedata)) g <- lm(Life.Exp ~ ., data=statedata) step(g) library(leaps) b<-regsubsets(Life.Exp~.,data=statedata) (rs <- summary(b)) plot(2:8,rs$cp,xlab="No. of Parameters",ylab="Cp Statistic") abline(0,1) plot(2:8,rs$adjr2,xlab="No. of Parameters",ylab="Adjusted R-square") h <- lm.influence(g)$hat names(h) <- state.abb rev(sort(h)) b<-regsubsets(Life.Exp~.,data=statedata,subset=(state.abb!="AK")) rs <- summary(b) rs$which[which.max(rs$adjr),] stripchart(data.frame(scale(statedata)),vertical=TRUE,method="jitter") b<-regsubsets(Life.Exp~log(Population)+Income+Illiteracy+Murder+HS.Grad+Frost+log(Area),statedata) rs <- summary(b) rs$which[which.max(rs$adjr),]