library(faraway) data(eco) plot(income ~ usborn, data=eco, xlab="Proportion US born", ylab="Mean Annual Income") g <- lm(income ~ usborn, eco) summary(g) plot(income ~ usborn, data=eco, xlab="Proportion US born", ylab="Mean Annual Income",xlim=c(0,1),ylim=c(15000,70000),xaxs="i") abline(coef(g)) data(chredlin) chredlin summary(chredlin) par(mfrow=c(2,3)) for(i in 1:6) stripchart(chredlin[,i],main=names(chredlin)[i],vertical=TRUE,method="jitter") par(mfrow=c(1,1)) pairs(chredlin) summary(lm(involact ~ race,chredlin)) plot(involact ~ race, chredlin) abline(lm(involact ~ race, chredlin)) plot(fire ~ race, chredlin) abline(lm(fire ~ race, chredlin)) g <- lm(involact ~ race + fire + theft + age + log(income), chredlin) summary(g) plot(fitted(g),residuals(g),xlab="Fitted",ylab="Residuals") abline(h=0) qqnorm(residuals(g)) qqline(residuals(g)) gi <- influence(g) qqnorml(gi$coef[,4]) halfnorm(cooks.distance(g)) range(rstudent(g)) chredlin[c(6,24),] g <- lm(involact ~ race + fire + theft + age + log(income),chredlin,subset=-c(6,24)) summary(g) prplot(g,1) prplot(g,2) chreduc <- chredlin[-c(6,24),] library(leaps) b<-regsubsets(involact~race + fire + theft + age + log(income),force.in=1,data=chreduc) (rs <- summary(b)) rs$adj g <- lm(involact ~ race + fire + theft + age, chredlin, subset=-c(6,24)) summary(g) galt <- lm(involact ~ race+fire+log(income),chredlin,subset=-c(6,24)) summary(galt) galt <- lm(involact ~ race+fire,chredlin,subset=-c(6,24)) summary(galt) g <- lm(involact ~ race + fire + theft + age, chredlin) summary(g) g <- lm(involact ~ race+fire+theft+age, subset=(side == "s"), chredlin) summary(g) g <- lm(involact ~ race+fire+theft+age, subset=(side == "n"), chredlin) summary(g)