postscript ("c:/books/multilevel/deathpolls.ps", horizontal=TRUE) par (mar=c(5,5,4,2)+.1) polls <- matrix (scan("polls.dat"), ncol=5, byrow=TRUE) support <- polls[,3]/(polls[,3]+polls[,4]) year <- polls[,1] + (polls[,2]-6)/12 plot (year, support*100, xlab="Year", ylim=c(min(100*support)-1, max(100*support)+1), ylab="Percentage support for the death penalty", cex=2, cex.main=2, cex.axis=2, cex.lab=2, pch=20) for (i in 1:nrow(polls)) lines (rep(year[i],2), 100*(support[i]+c(-1,1)*sqrt(support[i]*(1-support[i])/1000))) dev.off()