gilmour.slatehall | R Documentation |
Yields for a trial at Slate Hall Farm in 1978.
A data frame with 150 observations on the following 5 variables.
row
row
col
column
yield
yield (grams/plot)
gen
genotype factor, 25 levels
rep
rep factor, 6 levels
The trial was of spring wheat at Slate Hall Farm in 1978. The experiment was a balanced lattice with 25 varieties in 6 replicates. The 'rep' labels are arbitrary (no rep labels appeared in the source data). Each row within a rep is an incomplete block. The plot size was 1.5 meters by 4 meters.
Field width: 10 plots x 4 m = 40 m
Field length: 15 plots x 1.5 meters = 22.5 m
Arthur R Gilmour and Brian R Cullis and Arunas P Verbyla (1997). Accounting for natural and extraneous variation in the analysis of field experiments. Journal of Agricultural, Biological, and Environmental Statistics, 2, 269-293. https://doi.org/10.2307/1400446
None.
## Not run:
library(agridat)
data(gilmour.slatehall)
dat <- gilmour.slatehall
libs(desplot)
desplot(dat, yield ~ col * row,
aspect=22.5/40, num=gen, out1=rep, cex=1,
main="gilmour.slatehall")
if(require("asreml", quietly=TRUE)) {
libs(asreml,lucid)
# Model 4 of Gilmour et al 1997
dat <- transform(dat, xf=factor(col), yf=factor(row))
dat <- dat[order(dat$xf, dat$yf), ]
m4 <- asreml(yield ~ gen + lin(row), data=dat,
random = ~ dev(row) + dev(col),
resid = ~ ar1(xf):ar1(yf))
# coef(m4)$fixed[1] # linear row
# [1] 31.72252 # (sign switch due to row ordering)
lucid::vc(m4)
## effect component std.error z.ratio bound
## dev(col) 2519 1959 1.3 P 0
## dev(row) 20290 10260 2 P 0
## xf:yf(R) 23950 4616 5.2 P 0
## xf:yf!xf!cor 0.439 0.113 3.9 U 0
## xf:yf!yf!cor 0.125 0.117 1.1 U 0
plot(varioGram(m4), main="gilmour.slatehall")
}
## End(Not run)
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