Histogram

Load data

library(foreign)
ceosal1<-read.dta("http://fmwww.bc.edu/ec-p/data/wooldridge/ceosal1.dta")

Extract ROE to single vector

ROE <- ceosal1$roe

Subfigure (a): histogram (counts)

hist(ROE)

Subfigure (b): histogram (densities, explicit breaks)

hist(ROE, breaks=c(0,5,10,20,30,60) )