labdsv (version 1.2-0)

tabdev: Table Deviance

Description

Calculates the species (column-wise) and total deviance of a classified vegetation data frame

Usage

tabdev(taxa,clustering,nitr=1000)

Arguments

taxa

a vegetation (or other taxon) data frame

clustering

an integer vector specifying class membership for each plot

nitr

number of iterations to permute the data

Value

• a list with components:
• spcdev
  a dataframe with columns species, deviance, p-value
• totdev
  total table deviance

Details

Calculates the relative abundance of taxa in classes, and then calculates the deviance associated with that taxon. Total table deviance is simply the sum of species deviances. It calculates the probability of obtaining as low a deviance as observed by permuting the species values nitr-1 times. The p-val is then calculated as (n+1)/nitr where n is the number of cases with values as low or lower than observed.

References

http://ecology.msu.montana.edu/labdsv/R

See Also

duleg, duarm

Examples

data(bryceveg) # retrieves a vegetation data frame
    clust <- sample(1:5,nrow(bryceveg),replace=TRUE)
    tabdev(bryceveg,clust)