cochran.latin {agridat} | R Documentation

## Latin square design in wheat

### Description

Six wheat plots were sampled by six operators and shoot heights measured. The operators sampled plots in six ordered sequences. The dependent variate was the difference between measured height and true height of the plot.

### Format

A data frame with 36 observations on the following 4 variables.

`row`

  row

`col`

  column

`operator`

  operator factor

`diff`

  difference between measured height and true height

### Source

Cochran, W.G. and Cox, G.M. (1957), Experimental Designs, 2nd ed., Wiley and Sons, New York.

### Examples

    data(cochran.latin)
    dat <- cochran.latin

    if(require(desplot)){
      desplot(diff~col*row, dat,
              text=operator, cex=1, # aspect unknown
              main="cochran.latin")
    }

    dat <- transform(dat, rf=factor(row), cf=factor(col))
    aov.dat <- aov(diff ~ operator + Error(rf*cf), dat)
    summary(aov.dat)
    model.tables(aov.dat, type="means")

[Package agridat version 1.16 Index]