agridat (version 1.27)

hutchinson.cotton.uniformity: Uniformity trial of cotton

Description

Uniformity trial of cotton harvested in 1941

Usage

data("hutchinson.cotton.uniformity")

Format

A data frame with 2000 observations on the following 3 variables.

row

row ordinate

col

column ordinate

yield

yield per plant, grams

Details

The data are lint yield from single plants in a cotton uniformity trial in St. Vincent in 1940-41. The experiment was planted in 50 rows with 40 plants in each row. The spacing was 1.5 feet within rows and 4 feet between rows.

Field length: 40 plants * 1.5 feet = 60 feet

Field width: 50 columns * 4 feet = 200 feet

This data was made available with special help from the staff at Rothamsted Research Library.

Data provenance: Rothamsted library scanned the paper documents to pdf. K.Wright used the pdf to manually type the values into an Excel file and checked the hand-typed values. Plants marked as "Dead" on the PDF were left blank. There were 6 numbers that were illegible in the PDF. These were also left blank.

References

A. C. Brewer and R. Mead (1986). Continuous Second Order Models of Spatial Variation with Application to the Efficiency of Field Crop Experiments. Journal of the Royal Statistical Society. Series A (General), 149(4), 314–348. See page 325. http://doi.org/10.2307/2981720

Examples

if (FALSE) {
  library(agridat)
  data(hutchinson.cotton.uniformity)
  dat <- hutchinson.cotton.uniformity
  
  require(desplot)
  desplot(dat, yield ~ col*row,
          tick=TRUE, flip=TRUE, aspect=(40*1.5)/(50*4), # true aspect
          main="hutchinson.cotton.uniformity")
}