This data set gives the abundance of 32 mollusk species in 163 samples. For each sample, 4 additional covariates are known.

mollusk

## Format

A list with 2 two data frames:

Abundance

a 163 x 32 data frame of abundancies/counts (163 samples and 32 mollusk species)

Covariate

a 163 x 4 data frame of covariates:

site

a factor with 8 levels indicating the sampling site

season

a factor with 4 levels indicating the season

method

a factor with 2 levels for the method of sampling - wood or string

duration

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 prepare_data(). Original data set has been extracted from ade4.

## Source

Data from Richardot-Coulet, Chessel and Bournaud.

## References

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.

prepare_data()
data(mollusk)
mollusc <- prepare_data(mollusk$Abundance, mollusk$Covariate)