Babies 1: figure 1.3

# code for drawing the histogram of mother's height for 1214 mothers in the CHDS subset
ht = bab2$height
ht = ht[ht != 99] # 99 means missing value
h=hist(ht, breaks=seq(50,75,1), plot=F)
h$counts = 100*h$density
plot(h, xlab="Height (inches)", ylab="Percent per inch", border="white", col="gray20", main="")