theobald.barley {agridat}

Multi-environment trial of barley, multiple years & fertilizer levels

Description

Barley yields at multiple locs, years, fertilizer levels

Usage

data("theobald.barley")

Format

A data frame with 105 observations on the following 5 variables.

yield

yield, tonnes/ha

gen

genotype

loc

location, 5 levels

nitro

nitrogen kg/ha

year

year, 2 levels

Details

Theobald and Talbot used BUGS to fit a fully Bayesian model for yield response curves.

Locations of the experiment were in north-east Scotland.

Assumed nitrogen cost 400 pounds per tonne. Grain prices used were 100, 110, and 107.50 pounds per tonne for Georgie, Midas and Sundance.

Source

Chris M. Theobald and Mike Talbot, (2002). The Bayesian choice of crop variety and fertilizer dose. Appl Statistics, 51, 23-36. https://doi.org/10.1111/1467-9876.04863

Data provided by Chris Theobald and Mike Talbot.

Examples

## Not run: 

library(agridat)

data(theobald.barley)
dat <- theobald.barley
dat <- transform(dat,  env=paste(loc,year,sep="-"))
dat <- transform(dat, income=100*yield - 400*nitro/1000)

libs(lattice)
xyplot(income~nitro|env, dat, groups=gen, type='b',
       auto.key=list(columns=3), main="theobald.barley")


## End(Not run)