Grass: The effects of fertilizers on coastal Bermuda grass

In glmtoolbox: Set of Tools to Data Analysis using Generalized Linear Models

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.

glmtoolbox documentation built on Sept. 11, 2024, 7:32 p.m.