Cushing's syndrome is a hypertensive disorder associated with over-secretion of cortisol by the adrenal gland. The observations are urinary excretion rates of two steroid metabolites.
Cushings data frame has 27 rows and 3 columns:
urinary excretion rate (mg/24hr) of Tetrahydrocortisone.
urinary excretion rate (mg/24hr) of Pregnanetriol.
underlying type of syndrome, coded
a (adenoma) ,
c (carcinoma) or
u for unknown.
J. Aitchison and I. R. Dunsmore (1975) Statistical Prediction Analysis. Cambridge University Press, Tables 11.1–3.
Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.