| Grass {glmtoolbox} | R Documentation |
The effects of fertilizers on coastal Bermuda grass
Description
These data arose from a 4^3 factorial experiment with the three major plant nutrients, nitrogen (N), phosphorus (P), and potassium (K), on the
yield of coastal Bermuda grass. The experiment was performed to produce a response surface for the effects of the three nutrients, so that an optimal
dressing could be predicted. The grass was cut about every five weeks and oven-dried.
Usage
data(Grass)
Format
A data frame with 64 rows and 4 variables:
- Nitrogen
a numeric vector indicating the Nitrogen level, in lb/acre.
- Phosphorus
a numeric vector indicating the Phosphorus level, in lb/acre.
- Potassium
a numeric vector indicating the Potassium level, in lb/acre.
- Yield
a numeric vector indicating the yields, in tons/acre.
References
Welch L.F., Adams W.E., Carmon J.L. (1963) Yield Response Surfaces, Isoquants, and Economic Fertilizer Optima for Coastal Bermuda grass. Agronomy Journal, 55, 63-67.
McCullagh P., Nelder J.A. (1989). Generalized Linear Models. 2nd Edition. Chapman and Hall, London.
Wei B.C. (1998). Exponential Family Nonlinear Models. Springer, Singapore.