agridat (version 1.23)

mercer.mangold.uniformity: Uniformity trial of mangolds

Description

Uniformity trial of mangolds at Rothamsted Experiment Station, England, 1910.

Usage

data("mercer.mangold.uniformity")

Format

A data frame with 200 observations on the following 4 variables.

row

row

col

column

roots

root yields, pounds

leaves

leaf yields, pounds

Details

Grown in 1910.

Each plot was 3 drills, each drill being 2.4 feet wide. Plots were 1/200 acres, 7.2 feet by 30.25 feet long The "length of the plots runs with the horizontal lines of figures [in Table I], this being also the direction of the drills across the field."

Field width: 10 plots * 30.25ft = 302.5 feet

Field length: 20 plots * 7.25 ft = 145 feet

References

McCullagh, P. and Clifford, D., (2006). Evidence for conformal invariance of crop yields, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Science, 462, 2119--2143. https://doi.org/10.1098/rspa.2006.1667

Examples

if (FALSE) {

library(agridat)
  
  data(mercer.mangold.uniformity)
  dat <- mercer.mangold.uniformity
  
  libs(desplot)
  desplot(dat, leaves~col*row,
          aspect=145/302, # true aspect
          main="mercer.mangold.uniformity - leaves")

  libs(desplot)
  desplot(dat, roots~col*row,
          aspect=145/302, # true aspect
          main="mercer.mangold.uniformity - roots")

  libs(lattice)
  xyplot(roots~leaves, data=dat)
  
}