christidis.wheat.uniformity {agridat} | R Documentation

## Uniformity trial of wheat

### Description

Uniformity trial of wheat at Cambridge, UK in 1931.

### Usage

    data("christidis.wheat.uniformity")

### Format

A data frame with 288 observations on the following 3 variables.

`row`

  row

`col`

  column

`yield`

  yield

### Details

Two blocks, 24 rows each. In block A, each 90-foot row was divided into 12 units, each unit 7.5 feet long. Rows were 8 inches wide.

Field width: 12 units * 7.5 feet = 90 feet

Field length: 24 rows * 8 inches = 16 feet

### Source

Christidis, Basil G (1931). The importance of the shape of plots in field experimentation. The Journal of Agricultural Science, 21, 14-37. Table VI, p. 28. http://dx.doi.org/10.1017/S0021859600007942

### References

None

### Examples

    ## Not run:

      data(christidis.wheat.uniformity)
      dat <- christidis.wheat.uniformity

      # sum(dat$yield) # Matches Christidis

      require(desplot)
      desplot(yield ~  col*row, data=dat,
              flip=TRUE, aspect=16/90, # true aspect
              main="christidis.wheat.uniformity")

    ## End(Not run)

[Package agridat version 1.16 Index]