Entering edit mode
>Date: Thu, 22 Sep 2005 07:38:19 +0200
>From: "Hoen, P.A.C. 't " <p.a.c._t_hoen at="" lumc.nl="">
>Subject: [BioC] LIMMA: duplicate correlation
>To: <bioconductor at="" stat.math.ethz.ch="">
>
>Dear all,
>I am analysing results from a spotted microarray with 9,600 features,
>spotted in duplicate.
>When I calculate the duplicate correlation, as follows:
>
> cor <- duplicateCorrelation(datanorm_ordered, design,
ndups=2)
>
>I get the following error message:
>#5: Too much damping - convergence tolerance not achievable in:
>glmgam.fit(dx, dy, start = start, tol = tol, maxit = maxit, trace =
trace)
This is not an error message, this is a WARNING. As I have said many
times
on this list, getting a small number of warning messages from
duplicateCorrelation() is not a problem. Ignore it.
Gordon
>The consensus correlation coefficient is low (0.100) and also the
>distribution of correlation coefficients is between -0.1 and 0.5.
>
>Still, I seem to get reasonable results from the model fit on the 8
arrays.
>Does anyone know what the problem is here?
>
>Thanks a lot,
>Peter-Bram