ordi.focal.drop {ordiBreadth}

ordi.focal.drop

Description

This function computes the ordinated host breadth based on ordination where each herbivore is excluded from the ordination.

Usage

ordi.focal.drop(dat, dist.method = "jaccard")

Arguments

dat

A matrix of diet associations. Rows are herbivores and columns are diet items.

dist.method

Dissimilarity index passed on to vegdist in the vegan package.

Value

A list containing the following:

species

Name of herbivore species (row name of dat

ODB

Ordinated diet breadth

ODB.scaled

Scaled ordinated diet breadth

focal.distances

Distance to each diet item from herbivore centroid based on ordination excluding focal herbivore

focal.breadth

Ordinated diet breadth of herbivore based on ordination where focal herbivore is excluded

focal.scale.factor

The ordinated diet breadth of an extreme generalist in the ordinated space when focal herbivore is excluded from the ordination

focal.scale.breadth

Scaled ordinated diet breadth of herbivore based on ordination where focal herbivore is excluded

Author(s)

James Fordyce

References

Fordyce, J.A., C.C. Nice, C.A. Hamm, & M.L. Forister. Quantifying diet breadth through ordination of host association. Ecology

Examples

testdata<-	
	c(		
			0,0,0,0,1,0,0,0,0,0,
			0,0,0,0,0,0,1,1,0,0,
			1,1,1,0,0,0,0,0,0,0,
			0,0,0,0,1,1,0,1,0,1,
			1,1,1,0,0,0,1,0,0,0,
			1,1,0,0,1,0,1,0,0,0,
			0,0,0,1,0,0,1,0,1,1,
			1,0,1,0,1,1,0,0,0,1, 
			1,1,0,0,1,0,0,1,1,1,
			1,1,1,0,1,1,0,1,1,1) 


dat<-array(dim=c(10,10),data=testdata)
dat<-t(dat)
colnames(dat)<-paste("",LETTERS[1:10],sep="")
rownames(dat)<-paste("bug",1:10,sep="")


ordi.focal.drop(dat)