problem-2.34

problem-2.34  The graphics can be produced with these commands:
> data(DDT, package="MASS")     # load from MASS package
> hist(DDT)
> boxplot(DDT)
    
The histogram shows the data to be roughly symmetric, with one outlying value, so the mean and median should be similar and the standard deviation about three-quarters the IQR. The median and IQR can be identified on the boxplot giving estimates of 3.2 for the mean and a standard deviation a little less than 0.5. We can check with this command:
> c(mean(DDT), sd(DDT))
[1] 3.3280 0.4372