agridat (version 1.16)

mead.turnip: Density/spacing experiment for turnips in 3 blocks.

Description

Density/spacing experiment for turnips in 3 blocks.

Usage

data("mead.turnip")

Format

A data frame with 60 observations on the following 4 variables.

yield

log yield (pounds/plot)

block

block

spacing

row spacing, inches

density

density of seeds, pounds/acre

Details

An experiment with turnips, 3 blocks, 20 treatments in a factorial arrangement of 5 seeding rates (density) and 4 widths (spacing).

References

H. P. Piepho, R. N. Edmondson. (2018). A tutorial on the statistical analysis of factorial experiments with qualitative and quantitative treatment factor levels. Jour Agronomy and Crop Science, 8, 1-27. https://doi.org/10.1111/jac.12267

Examples

# NOT RUN {
data(mead.turnip)
dat <- mead.turnip

dat$ratef <- factor(dat$density)
dat$widthf <- factor(dat$spacing)

m1 <- aov(yield ~ block + ratef + widthf + ratef:widthf, data=dat)
anova(m1) # table 12.10 in Mead

# Similar to Piepho fig 10
if(require(lattice)) {
  xyplot(yield ~ log(spacing)|ratef, data=dat,
         auto.key=list(columns=5),
         main="mead.turnip - log(yield) for each density",
         group=ratef)
}
# }