mcclelland.corn.uniformity {agridat} | R Documentation

## Uniformity trial of corn

### Description

Uniformity trial of corn at Arkansas Experiment Station, 1925.

### Usage

    data("mcclelland.corn.uniformity")

### Format

A data frame with 438 observations on the following 3 variables.

`row`

  row

`col`

  column

`yield`

  yield

### Details

A uniformity trial of corn in 1925 at the Arkansas Experimental Station.

Field width = 66ft * 2 = 132 feet.

Field length = 219 rows * 44 inches / 12 inches/ft = 803 ft.

Note: In the source document, table 2, first 'west' column and second-to-last row (page 822), the value 1.40 is assumed to be a typographical error and was changed to 14.0 for this data.

### Source

McClelland, Chalmer Kirk (1926). Some determinations of plat variability. Agronomy Journal, 18, 819-823. http://doi.org/10.2134/agronj1926.00021962001800090009x

### References

None

### Examples

    ## Not run:

      data(mcclelland.corn.uniformity)
      dat <- mcclelland.corn.uniformity

      # McClelland table 3, first row, gives 11.2
      # Probable error = 0.67449 * sd(). Relative to mean.
      0.67449 * sd(dat$yield)/mean(dat$yield) # 11.2

      require(desplot)
      desplot(yield ~ col*row, dat,
              flip=TRUE,
              aspect=(219*44/12)/132, # true aspect, 219 rows * 44 inches x 132 feet
              main="mcclelland.corn.uniformity")

    ## End(Not run)

[Package agridat version 1.16 Index]