vr {tsvr}

Compute the classic or Loreau-de Mazancourt variance ratio

Description

This function is used to compute the classical or Loreau-de Mazancourt variance ratio for a community in a single plot.

Usage

vr(X, method = "classic")

Arguments

X

A matrix with counts or densities arranged in species by time steps

method

If "classic" (default), use the classical method. If "LdM", use the Loreau-de Mazancourt method (see reference).

Value

vr returns the value of variance ratio

Author(s)

Lei Zhao, [e-mail]; Daniel Reuman, [e-mail]

References

Loreau & Mazancourt, Species Synchrony and Its Drivers: Neutral and Nonneutral Community Dynamics in Fluctuating Environments. 2008, Am. Nat. 172(2)

Zhao et al, (In prep) Decomposition of the variance ratio illuminates timescale-specific population and community variability.

Peterson, Stability of species and of community for the benthos of two lagoons. 1975, Ecology, 56, 958-965.

See Also

vrf, vreq, vreq_classic, vreq_LdM, browseVignettes("tsvr")

Examples

X<-matrix(runif(200,1,100), 10, 20)
vr(X, method="LdM")
vr(X, method="classic")