The frets data frame has 25 rows and 4 columns.
The data consist of measurements of the length and breadth of the heads of pairs of adult brothers in 25 randomly sampled families. All measurements are expressed in millimetres.
fretsThis data frame contains the following columns:
l1The head length of the eldest son.
b1The head breadth of the eldest son.
l2The head length of the second son.
b2The head breadth of the second son.
Davison, A.C. and Hinkley, D.V. (1997) Bootstrap Methods and Their Application. Cambridge University Press.
Whittaker, J. (1990) Graphical Models in Applied Multivariate Statistics. John Wiley.