[R] Suggestions: Terminology & Pkgs for following spectra over time

[Katharine Mullen]

Dear Bryan,

For work in that general direction, look at the R News that was on 'R in
chemistry' (Volume 6/3, August 2006,
http://www.r-project.org/doc/Rnews/Rnews_2006-3.pdf) and the special vol.
of the Journal of Statistical Software on 'Spectroscopy and Chemometrics
in R' (vol 18, http://www.jstatsoft.org/v18)

For ideas about modeling spectra resolved in time and frequency, the
papers of Sabine van Huffel at K U Leuven may be of interest
(http://www.esat.kuleuven.be/~sistawww/cgi-bin/newsearch.pl?Name=Van+Huffel+S)

If you decide that you want to describe the time domain with a parametric
model, then look at the package TIMP (and perhaps contact me off list).

On Wed, 16 Apr 2008, Bryan Hanson wrote:

> Hi Folks... No code to troubleshoot here.  I need some suggestions about the
> right terminology to use in further searching, and any suggestions about R
> pkgs that might be appropriate.
>
> I am in the planning stages of a project in which IR, NMR and other spectra
> (I'm a chemist) would be collected on various samples, and individual
> samples would be followed over time.  The spectra will be feature
> rich/complex, so one can't see the changes by visual inspection.  The
> spectra are basically 2D matrices: peaks as a function of frequencies.  So
> the data set is in the form of spectra of a single sample over time, for
> multiple samples.
>
> I am wondering about methods & R pkgs that can be used to analyze changes in
> the spectra over time.  For instance, I would like to find specific peaks
> that are changing over time, sets of peaks that are changing in a correlated
> way over time etc.  I'd like to do this in an efficient and statistically
> valid way.  What I am thinking of is somewhat like a time series, somewhat
> like image analysis (but only 2D), but it's not quite either of those and I
> need to know what it's really called to investigate further.
>
> Any suggestions as to R pkgs and key words/phrases will be appreciated.
>
> TIA, Bryan
> *************
> Bryan Hanson
> Professor of Chemistry & Biochemistry
> DePauw University, Greencastle Indiana USA
>
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