This data set gives the abundance of 32 mollusk species in 163 samples. For each sample, 4 additional covariates are known.
A list with 2 two data frames:
a 163 x 32 data frame of abundancies/counts (163 samples and 32 mollusk species)
a 163 x 4 data frame of covariates:
a factor with 8 levels indicating the sampling site
a factor with 4 levels indicating the season
a factor with 2 levels for the method of sampling - wood or string
a numeric with 3 levels for the time of exposure in week
In order to prepare the data for using formula in multivariate analysis (multiple outputs and inputs), use
Original data set has been extracted from ade4.
Data from Richardot-Coulet, Chessel and Bournaud.
Richardot-Coulet, M., Chessel D. and Bournaud M. (1986) Typological value of the benthos of old beds of a large river. Methodological approach. Archiv fùr Hydrobiologie, 107, 363–383.
data(mollusk) mollusc <- prepare_data(mollusk$Abundance, mollusk$Covariate) #> Warning: Sample(s) 134 and 137 and 145 and 146 dropped for lack of positive counts.