On Fri, 7 Jul 2006, lamp at few.eur.nl wrote:
> Hello,
>
> I found a little BUG in loess <stats>. It does not receive the
iterations
> parameter.
Please provide an example demonstrating this 'BUG', as we do ask you to
do, along with basic information like your name, the version of R, the
platform ....
> It can be debugged in the following way:
(Not in any sense of `debugged' that my dictionary mentions.)
> THIS IS AN EXCERPT FROM THE CODE:
>
> ....
>
> fit <- simpleLoess(y, x, w, span, degree, parametric, drop.square,
> normalize, control$statistics, control$surface, control$cell,
> iterations, control$trace.hat)
>
> Replace argument iterations with control$iterations.
Why? The code contains a few lines earlier
iterations <- if(family=="gaussian") 1 else control$iterations
which is the intention. ?loess.control does say
iterations: the number of iterations used in robust fitting.
^^^^^^
> I found also remarkable differences when comparing loess with PROC LOESS
> (in SAS) using the same parameters and variables. It really confuses me.
> Where can I report this?
R-bugs is not a place to ask questions, but bugs in SAS can be reported to
SAS inc.
--
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