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Split-plot experiment of rice, with subsamples

Format

A data frame with 186 observations on the following 5 variables.

time

time factor, T1-T4

manage

management, M1-M6

rep

rep/block, R1-R3

sample

subsample, S1-S2

height

plant height (cm)

Details

A split-plot experiment in three blocks. Whole-plot is 'management', sub-plot is 'time' of application, with two subsamples. The data are the heights, measured on two single-hill sampling units in each plot.

Used with permission of Kwanchai Gomez.

Source

Gomez, K.A. and Gomez, A.A.. 1984, Statistical Procedures for Agricultural Research. Wiley-Interscience. Page 481.

Examples

if (FALSE) { # \dontrun{

library(agridat)
data(gomez.splitplot.subsample)
dat <- gomez.splitplot.subsample

libs(HH)
interaction2wt(height ~ rep + time + manage, data=dat,
               x.between=0, y.between=0,
               main="gomez.splitplot.subsample - plant height")


# Management totals, Gomez table 6.8
# tapply(dat$height, dat$manage, sum)

# Gomez table 6.11 analysis of variance
m1 <- aov(height ~ rep + manage + time + manage:time +
          Error(rep/manage/time), data=dat)
summary(m1)
## Error: rep
##     Df Sum Sq Mean Sq
## rep  2   2632    1316

## Error: rep:manage
##           Df Sum Sq Mean Sq F value Pr(>F)
## manage     7   1482  211.77   2.239 0.0944 .
## Residuals 14   1324   94.59
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

## Error: rep:manage:time
##             Df Sum Sq Mean Sq F value   Pr(>F)
## time         3  820.8  273.61   7.945 0.000211 ***
## manage:time 21  475.3   22.63   0.657 0.851793
## Residuals   48 1653.1   34.44
## ---
## Signif. codes:  0 '***' 0.001 '**' 0.01 '*' 0.05 '.' 0.1 ' ' 1

## Error: Within
##           Df Sum Sq Mean Sq F value Pr(>F)
## Residuals 96  167.4   1.744

} # }