[http://www.ats.ucla.edu/stat/_headers/header1.htm][http://www.ats.ucla.edu/stat/r/examples/alda/header.htm][http://www.ats.ucla.edu/stat/_headers/header2.htm]

R Textbook Examples
Applied Longitudinal Data Analysis: Modeling Change and Event Occurrence
by Judith D. Singer and John B. Willett
Chapter 9: A framework for investigating event occurrence

The examples on the page were written in R version 2.4.1. 

Fig. 9.1 on page 321.

teachers<-read.table("http://www.ats.ucla.edu/stat/examples/alda/teachers.csv", sep=",", header=T)
attach(teachers)
t0<-teachers$t[censor==0]
t1<-teachers$t[censor==1]
par(mfrow=c(1, 2), mar=c(3, 3, 1, 1), cex=0.7)
h0<-hist(t0, breaks=c(0:12),  plot=FALSE)
h1<-hist(t1, breaks=c(0:12),  plot=FALSE)
plot(h0, labels=TRUE, col="darkgray", ylim=c(0, 500), main=" ")
plot(h1, labels=TRUE, ylim=c(0, 500), col="darkgray", main=" ", ylab="")

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