williams.cotton.uniformity {agridat} | R Documentation |
Uniformity trial of cotton at Narrabri, New South Wales, 1984.
A data frame with 288 observations on the following 3 variables.
row
row
col
column
yield
lint yield, kg/ha divided by 10
Cotton uniformity trial grown at Narrabri, New South Wales, 1984-1985. Plots were 12m long, 1m apart, 12 rows by 24 columns, with an irrigation furrow between columns.
Field width: 24 plots * 1 m = 24 m
Field length: 12 plots * 12 m = 144 m
Williams, ER and Luckett, DJ. 1988. The use of uniformity data in the design and analysis of cotton and barley variety trials. Australian Journal of Agricultural Research, 39, 339-350. http://doi.org/10.1071/AR9880339
data(williams.cotton.uniformity) dat <- williams.cotton.uniformity if(require(desplot)){ desplot(yield ~ col*row, dat, aspect=144/24, # true aspect main="williams.cotton.uniformity") } # Smoothed contour/persp plot like Williams 1988 Fig 1a, 2a dat$fit <- fitted(loess(yield~col*row, dat, span=.5)) require("lattice") contourplot(fit~col*row, data=dat, aspect=144/24, region=TRUE, cuts=6, col.regions=RedGrayBlue, main="williams.cotton.uniformity") # wireframe(fit~col*row, data=dat, zlim=c(100, 250), # main="williams.cotton.uniformity") # Williams table 1 anova(aov(yield ~ factor(row) + factor(col), dat))