[R] Help: lda predict

[Shengzhe Wu]

I compared "posterior" of these three prediction results, they are a
little different.

The book you mentioned should be "Modern Applied Statistics with S.
4th edition". But this book has been borrowed out from our univeristy
library by someone else, and I have checked the book "Pattern
Recognition and Neural Networks" which does not mention these three
lda prediction methods.

Thanks you,
Shengzhe

On 8/26/05, Prof Brian Ripley <ripley at stats.ox.ac.uk> wrote:
> On Fri, 26 Aug 2005, Shengzhe Wu wrote:
> 
> > Thanks for your reply. Actually I called function as below.
> >
> > p1 = predict(object, newdata, dimen=1)
> > p2 = predict(object, newdata, dimen=1, method=debiased)
> > p3 = predict(object, newdata, dimen=1, method="predictive")
> 
> So why did you say something different?
> 
> > The MAP classification of prediction results by any method are the
> > same. I know what the method "plug-in" and "debiased" mean, but what
> > does the "vague prior" for the method "predictive" mean? what is
> > "vague" here?
> 
> Please do as we ask, and read the book for which this is supporting
> material (on p.339, to save you looking in the index).
> 
> >
> > Thank you,
> > Shengzhe
> >
> >
> >
> > On 8/26/05, Prof Brian Ripley <ripley at stats.ox.ac.uk> wrote:
> >> On Fri, 26 Aug 2005, Shengzhe Wu wrote:
> >>
> >>> I use lda (package: MASS) to obtain a lda object, then want to employ
> >>> this object to do the prediction for the new data like below:
> >>>
> >>> predict(object, newdata, dimen=1, method=c("plug-in", "predictive", "debiased"))
> >>
> >> That is not how you call it: when a character vector is given like that
> >> those are alternatives.  Do read the help page, as we ask.
> >>
> >>> What is the exact difference among the three methods? What is the
> >>> difference of prediction results when applying different method?
> >>
> >> This is stated on the help page.  If you are unfamiliar with the area,
> >> note that the posting guide points out that MASS is support software for a
> >> book and the explanations are in the book.  The help page also has
> >> references: please do read them (before posting).
> >>
> >>> PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
> >>
> >> --
> >> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> >> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> >> University of Oxford,             Tel:  +44 1865 272861 (self)
> >> 1 South Parks Road,                     +44 1865 272866 (PA)
> >> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
> >>
> >
> >
> 
> --
> Brian D. Ripley,                  ripley at stats.ox.ac.uk
> Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
> University of Oxford,             Tel:  +44 1865 272861 (self)
> 1 South Parks Road,                     +44 1865 272866 (PA)
> Oxford OX1 3TG, UK                Fax:  +44 1865 272595
>