Create a data set from the family lung function data described in Appendix A as follows. It will have three times the number of observations that the original data set has—the first third of the observations will be the mothers’ measurements, the second third those of the fathers, and the final third those of the oldest children. Perform a cluster analysis, first producing three groups and then two groups, using the variables AGE, HEIGHT, WEIGHT, FEV1, and FVC.

Do the mothers, fathers, and oldest children cluster on the basis of any of these variables?