Neter et al. (1996) described an experiment in which researchers investigated the confounding effect of gender and bone development on growth hormone therapy for prepubescent children. Gender had two levels: "M" and "F".
The bone development factor had three levels indicating the severity of growth impediment before therapy: 1 = severely depressed, 2 = moderately depressed, and 3 = mildly depressed.
At the start of the experiment 3 children were assigned to each of the six treatment combinations. However 4 of the children were unable to complete the experiment, resulting in an unbalanced design.
Usage
data(bone)
Arguments
source
Neter, J., Kutner, M. H., Nachtsheim, C. J., and Wasserman, W (1996) Applied linear Statistical Models. McGraw-Hill, Boston MA, USA.