agridat (version 1.16)

hunter.corn: Multi-environment trial of corn with nitrogen fertilizer

Description

Corn yield response to nitrogen

Format

A data frame with 54 observations on the following 4 variables.

nitro

nitrogen fertilizer, pound/acre

year

year

loc

location

yield

yield, bu/ac

Details

Experiments were conducted in eastern Oregon during the years 1950-1952.

Planting rates varied from 15,000 to 21,000 planter per acre.

References

James Leo Paschal, Burton Leroy French (1956). A method of economic analysis applied to nitrogen fertilizer rate experiments on irrigated corn. Tech Bull 1141. United States Dept of Agriculture. books.google.com/books?id=gAdZtsEziCcC&pg=PP1

Examples

# NOT RUN {
data(hunter.corn)
dat <- hunter.corn

dat <- transform(dat, env=factor(paste(loc,year)))

require(lattice)
xyplot(yield~nitro|env, dat, type='b',
main="hunter.corn - nitrogen response curves")

# }