corsten.interaction {agridat} | R Documentation

## Multi-environment trial of corn

### Description

The data is the yield (kg/acre) of 20 genotypes of corn at 7 locations.

### Format

A data frame with 140 observations on the following 3 variables.

`gen`

  genotype, 20 levels

`loc`

  location, 7 levels

`yield`

  yield, kg/acre

### Details

The data is used by Corsten & Denis (1990) to illustrate two-way clustering by minimizing the interaction sum of squares.

In their paper, the labels on the location dendrogram have a slight typo. The order of the loc labels shown is 1 2 3 4 5 6 7. The correct order of the loc labels is 1 2 4 5 6 7 3.

### Source

L C A Corsten and J B Denis, (1990). Structuring Interaction in Two-Way Tables By Clustering. Biometrics, 46, 207–215. Table 1. http://doi.org/10.2307/2531644

Used with permission of Jean-Baptiste Denis.

### Examples

    data(corsten.interaction)
    dat <- corsten.interaction

    if(require(reshape2)){
    m1 <- melt(dat, measure.var='yield')
    dmat <- acast(m1, loc~gen)

    # Corsten (1990) uses this data to illustrate simultaneous row and
    # column clustering based on interaction sums-of-squares.
    # There is no (known) function in R to reproduce this analysis
    # (please contact the package maintainer if this is not true).
    # For comparison, the 'heatmap' function clusters the rows and
    # columns _independently_ of each other.
    heatmap(dmat, main="corsten.interaction")
    }

[Package agridat version 1.16 Index]