Data from an experiment on the growth of turkeys. 60 pens of turkeys were grown with a similar diet, supplemented with a dose of methionine from one of three sources. The response is average pen weight. Recorded is dose, source, m, always 5 except for dose=0, average weight gain, and within group SS.
This data frame contains the following columns:
Dose: Amount of supplement as a percent of the total diet
Ave. weight gain, over all replications
A factor for the source of methionine, three levels numbers 1, 2 and 3.
Number of replications or pens
SD of the m pens with the same values of S and A.
R. D. Cook and J. Witmer (1985). A note on parameter-effects curvature. Journal of the American Statistical Association, 80, 872–878.
Weisberg, S. (2005). Applied Linear Regression, 3rd edition. New York: Wiley, Section 1.1.