dispersion {BAT} | R Documentation |
Average dissimilarity between any two species or individuals randomly chosen in a community.
dispersion( comm, tree, distance, func = "originality", abund = TRUE, relative = TRUE )
comm |
A sites x species matrix, with either abundance or incidence data. If missing, the dispersion using the full tree or distance matrix is calculated. |
tree |
A phylo or hclust object (used only for PD or FD) or alternatively a species x traits matrix or data.frame to build a functional tree. |
distance |
A dist object representing the phylogenetic or functional distance between species. |
func |
Calculate dispersion using originality (default), uniqueness or contribution. |
abund |
A boolean (T/F) indicating whether dispersion should be calculated using individuals (T) or species (F). |
relative |
A boolean (T/F) indicating whether dispersion should be relative to the maximum distance between any two species in the tree or distance matrix. |
If abundance data is used and a tree is given, dispersion is the quadratic entropy of Rao (1982). If abundance data is not used but a tree is given, dispersion is the phylogenetic dispersion measure of Webb et al. (2002).
A vector of values per site (or a single value if no comm is given).
Rao, C.R. (1982) Diversity and dissimilarity coefficients: a unified approach. Theoretical Population Biology, 21: 24-43.
Webb, C.O., Ackerly, D.D., McPeek, M.A. & Donoghue, M.J. (2002) Phylogenies and community ecology. Annual Review of Ecology and Systematics, 33: 475-505.
comm <- matrix(c(1,2,0,0,0,1,1,0,0,0,0,2,2,0,0,0,0,1,1,1), nrow = 4, byrow = TRUE) distance <- dist(c(1:5), method="euclidean") tree <- hclust(distance, method="average") dispersion(tree = tree) dispersion(distance = distance) dispersion(comm, tree) dispersion(comm, tree, abund = FALSE) dispersion(comm, tree, abund = FALSE, relative = FALSE)