[R-sig-eco] vegdist: "binomial", is it the scale-invariant version?

[Pierre THIRIET]

Dear all,

Please, could someone confirm that vegdist(X, meth="binomial") is the 
binomial deviance *scaled* (i.e. the scale-invarient version of 
"binomial deviance")

I want to use the dissimilarity "binomial deviance *scaled*", described 
by Anderson and Millar (2004) as
where

"scaled" since it is the scale-invarient version of the "binomial 
deviance" (by dividing by n/k/), also described by Anderson and Millar 
(2004)


vegdist implements the "binomial index" as
d[jk] = sum*(*x[ij]*log(x[ij]/n[i]) + x[ik]*log(x[ik]/n[i]) - 
n[i]*log(1/2)*)*/n[i]    , where n[i] = x[ij] + x[ik]

It seems therefore that is the "binomial deviance scaled", whright ?

I thank you in advance,

cheers,
Pierre



Anderson, M.J. and Millar, R.B. (2004). Spatial variation and effects of 
habitat on temperate reef fish assemblages in northeastern New Zealand. 
/Journal of Experimental Marine Biology and Ecology/ 305, 191--221.