snails:
Dataset - Growth rates of snails on large boulders on different rock shores.
Description
This design was extracted from Underwood (1997) but data are artificial. Snails were transplanted from origin to different shores. Several boulders were used on each shore. Cages with snail of each origin on each boulder were replicated. All factors (origin, shore, boulder and cage) are random.
Usage
data(snails)
Arguments
Format
A data frame with 240 observations on the following 6 variables.
origin
a random factor with levels O1O2
shore
a random factor with levels S1S2S3S4 orthogonal to origin
boulder
a random factor with levels B1B2B3 nested in shore
cage
a random factor with levels C1C2 nested in the combination of boulder and origin
replicate
Sample size
growth
response variable
References
Underwood, A.J. 1997. Experiments in Ecology: Their Logical Design and Interpretation Using Analysis of Variance. Cambridge University Press, Cambridge.