asim3_f: Abundance swap within rows

In irhoppe/cooccur: Abundance Matrix Randomizations

Description

Randomizes an abundance matrix by reshuffling populations equiprobably among the nonempty cells of each row.

Usage

asim3_f(speciesData)

Arguments

speciesData

species-by-site abundance matrix

Details

Performs a series of abundance swaps within rows (species); equivalent to algorithm PR in Ulrich and Gotelli (2010), and to the Fortran subroutine pr in Ulrich (2008).

Preserves total matrix abundance and occurrences as well as species abundances (row totals), but allows site abundances (column totals) to vary equiprobably.

Value

shuffled abundance matrix

References

Ulrich, W. 2008. Program Co-Occurrence. Version 1.

Ulrich, W. and Gotelli, N.J. 2010. Null model analysis of species associations using abundance data. Ecology 91:3384-3397.

See Also

Other abundance matrix null models: asim10_f(), asim10(), asim11_f(), asim11(), asim12_f(), asim12(), asim13_f(), asim13(), asim14_f(), asim14(), asim1_f(), asim1(), asim2_f(), asim2(), asim3(), asim4_f(), asim4(), asim5_f(), asim5(), asim6_f(), asim6(), asim7_f(), asim7(), asim8_f(), asim8(), asim9_f(), asim9()

Examples

amat <- rmat(20,12) # creates a random 20 x 12 abundance matrix
asim3_f(amat)       # performs equiprobable asrow abundance swap algorithm

irhoppe/cooccur documentation built on Jan. 1, 2021, 4:23 a.m.