little.splitblock: Split-block experiment of sugar beets In agridat: Agricultural Datasets

Description

Split-block experiment of sugar beets.

Usage

 1 data("little.splitblock")

Format

A data frame with 80 observations on the following 6 variables.

row

row

col

column

yield

sugar beet yield, tons/acre

harvest

harvest date, weeks after planting

nitro

nitrogen, pounds/acre

block

block

Details

Four rates of nitrogen, laid out as a 4x4 Latin-square experiment.

Within each column block, the sub-plots are strips (across 4 rows) of 5 different harvest dates.

The use of sub-plots a s strips necessitates care when determining the error terms in the ANOVA table.

Note, Little has yield value of 22.3 for row 3, column I-H3. This data uses 23.3 in order to match the marginal totals given by Little.

Source

Thomas M. Little, F. Jackson Hills. (1978) Agricultural Experimentation

None.

Examples

 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 ## Not run: library(agridat) data(little.splitblock) dat <- little.splitblock # Match marginal totals given by Little. ## sum(dat\$yield) ## with(dat, tapply(yield,col,sum)) ## with(dat, tapply(yield,row,sum)) # Layout shown by Little figure 10.2 libs(desplot) desplot(dat, yield ~ col*row, out1=block, out2=col, col=nitro, cex=1, num=harvest, main="little.splitblock") # Convert continuous traits to factors dat <- transform(dat, R=factor(row), C=factor(block), H=factor(harvest), N=factor(nitro)) if(0){ libs(lattice) xyplot(yield ~ nitro|H,dat) xyplot(yield ~ harvest|N,dat) } # Anova table matches Little, table 10.3 m1 <- aov(yield ~ R + C + N + H + N:H + Error(R:C:N + C:H + C:N:H), data=dat) summary(m1) ## End(Not run)

agridat documentation built on Dec. 20, 2021, 9:07 a.m.