Multi-environment trial of 33 barley genotypes in 18 locations

data("lin.unbalanced")

Format

A data frame with 405 observations on the following 4 variables.

gen: genotype/cultivar
loc: location
yield: yield (kg/ha)
region: region

Details

Yield of six-row barley from the 1986 Eastern Cooperative trial

The named cultivars Bruce, Laurier, Leger are checks, while the other cultivars were tests. Cultivar names use the following codes. "A" is for Atlantic-Quebec. "O" is for "Ontario". "S" is second-year. "T" is third-year.

Source

C. S. Lin, M. R. Binns (1988). A Method for Assessing Regional Trial Data When The Test Cultivars Are Unbalanced With Respect to Locations. Canadian Journal of Plant Science, 68(4): 1103-1110. https://doi.org/10.4141/cjps88-130

References

None

Examples

# \dontrun{

library(agridat)
data(lin.unbalanced)
dat <- lin.unbalanced

# location maximum, Lin & Binns table 1
# aggregate(yield ~ loc, data=dat, FUN=max)

# location mean/index, Lin & Binns, table 1
dat2 <- subset(dat, is.element(dat$gen,
  c('Bruce','Laurier','Leger','S1','S2',
    'S3','S4','S5','S6','S7','T1','T2')))
aggregate(yield ~ loc, data=dat2, FUN=mean)
#>    loc    yield
#> 1  L01 6205.417
#> 2  L02 6562.000
#> 3  L03 4118.167
#> 4  L04 7203.583
#> 5  L05 3795.417
#> 6  L06 5440.583
#> 7  L07 5243.250
#> 8  L08 5419.500
#> 9  L09 6205.750
#> 10 L10 4186.583
#> 11 L11 3565.250
#> 12 L12 4027.583
#> 13 L13 4245.667
#> 14 L14 5061.750
#> 15 L15 4348.083
#> 16 L16 5424.583
#> 17 L17 3909.250
#> 18 L18 3123.833

libs(reshape2)
dat3 <- acast(dat, gen ~ loc, value.var="yield")
libs(lattice)
lattice::levelplot(t(scale(dat3)), main="lin.unbalanced", xlab="loc", ylab="genotype")

# calculate the superiority measure of Lin & Binns 1988.
# lower is better
locmax <- apply(dat3, 2, max, na.rm=TRUE)
P <- apply(dat3, 1, function(x) {
  sum((x-locmax)^2, na.rm=TRUE)/(2*length(na.omit(x)))
})/1000
P <- sort(P)
round(P) # match Lin & Binns 1988 table 2, column P
#>     O02      S4     O01     O10     O07     O06     O05     O08     O04      S5 
#>     110     121     142     150     171     199     203     223     316     338 
#>   Leger      S1     A04     O09     A06      T2      S2     A03      T1     O03 
#>     366     379     388     401     421     423     485     515     519     528 
#>      S7     A11      S6     A09     A07      S3     A05     A08     A10   Bruce 
#>     549     567     657     706     717     750     762     791     849     900 
#> Laurier     A02     A01 
#>     933    1134    1566 
# }