sfsmisc (version 0.9-4)

potatoes: Fisher's Potato Crop Data

Usage

data(potatoes)

source

Bennett, J. H. (1972) Collected Papers of R. A. Fischer vol.~II, 1925-31; The University of Adelaide.

Details

FIXME

References

T.Eden and R. A. Fisher (1929) Studies in Crop Variation. VI. Experiments on the Response of the Potato to Potash and Nitrogen. J. Agricultural Science 19, 201--213. Accessible from Bennett (1972), see above.

Examples

data(potatoes)
## See the experimental design:
with(potatoes, {
     cat("4 blocks of experiments;",
         "each does every (nitrogen,potash) combination (aka 'treat'ment) once.",
         '', sep="")
     print(ftable(table(nitrogen, potash, treat)))
     print(ftable(tt <- table(pos,potash,nitrogen)))
     tt[cbind(pos,potash,nitrogen)] <- as.character(treat)
     cat("The 4 blocks  pos = 1, 2, 3, 4:
")
     ftable(tt)
     })
## First plot:
with(potatoes, interaction.plot(potash,nitrogen, response=yield))

## ANOVAs:
summary(aov(yield ~ nitrogen * potash + Error(pos), data = potatoes))
    # "==>" can use simply
summary(aov(yield ~ nitrogen + potash + pos, data = potatoes))
    # and
summary(aov(yield ~ nitrogen + potash, data = potatoes))