EcoSimR (version 0.1.0)

c_score_var: CScoreVariance Co-occurrence Metric

Description

Takes a binary presence-absence matrix and returns the variance of the Stone and Roberts' (1990) C-score.

Usage

c_score_var(m = matrix(rbinom(100, 1, 0.5), nrow = 10))

Arguments

m

a binary presence-absence matrix in which rows are species and columns are sites.

Value

Returns the variance of the C-score calculated across all possible species pairs in the matrix.

Details

A large value of this variance implies that some species pairs in the matrix are strongly segregated (large C-score) and other species pairs are random or aggregated.

References

Stone, L. and A. Roberts. 1990. The checkerboard score and species distributions. Oecologia 85: 74-79.

Stone, L. and A. Roberts. 1992. Competitive exclusion, or species aggregation? An aid in deciding. Oecologia 91: 419-424.

See Also

c_score co-occurrence index.

Examples

varCScore <- c_score_var(m=matrix(rbinom(100,1,0.5),nrow=10))