[R] 2 LDA

[Steve Adams]

Hi,

I am using Partek for LDA analysis. For a binary
response variable, it generates 2 discriminant
functions, one for each of the 2 levels of the
response variable. And I can simply calculate 2
discriminant scores (say d1 and d2) for each sampples
using the 2 discriminant functions, then I can use the
following formula to compute the posterior probability
for the sample:

p1=exp(d1-d2)/(1+exp(d1-d2))
p2=1/(1+exp(d1-d2))

In R, the lda function only generates 1 discriminant
function, and exactly the same posterior probability
as the LDA function in Partek does.

My question is what's the difference (or relationship)
between the above 2 LDA functions, where I can find
the reference for the partek LDA function?

Thanks

Steve