These data have been introduced by Yates (1935) as an
example of a split-plot design. The treatment structure used in the
experiment was a 3$$4 full factorial, with three varieties of
oats and four concentrations of nitrogen. The experimental units were
arranged into six blocks, each with three whole-plots subdivided into
four subplots. The varieties of oats were assigned randomly to the
whole-plots and the concentrations of nitrogen to the subplots. All
four concentrations of nitrogen were used on each whole-plot.Pinheiro, J. C. and Bates, D. M. (2000), Mixed-Effects Models in S
and S-PLUS, Springer, New York. (Appendix A.15)
Venables, W. N. and Ripley, B. D. (1999) Modern Applied
Statistics with S-PLUS (3rd ed), Springer, New York.datasets