Carsten,

I'm trying to make sure I understand your question. You have taken cores
(from which you have tree-rings) from 2 species of trees, which are of 2
ages in 2 different soils - so eight different species*age*soil
"treatments". You also have climate data and element input data as
continuous variables.

What is the spatial and temporal resolution of the continuous variables?
(Are they measured at the level of individual trees, or at the level of
site? Are they measured in a time-series also, or only for one year?)

Eric Nord, Post Doctoral Scholar
Department of Horticulture
The Pennsylvania State University
222 Tyson Building, University Park, PA 16802
814-863-2313
ericnord@psu.edu

Get a bicycle. You will not regret it. If you live. - Mark Twain




On Jan 24, 2012, at 6:00 AM, r-sig-ecology-request@r-project.org wrote:

Date: Tue, 24 Jan 2012 11:16:55 +0100
From: C Hess <13184@stud.leuphana.de>
To: r-sig-ecology@r-project.org
Subject: [R-sig-eco] model for tree-ring analysis
Message-ID: <4F1E8517.4080603@stud.leuphana.de>
Content-Type: text/plain; charset=ISO-8859-15; format=flowed

Dear Listusers,

i had some difficulties in finding a proper model in R for my work in a
tree-ring analysis. Still working on statistical basics I'am asking here
for some hints or tipps which will help me on my way to find a model I
could use in R.

My data sample is a time-series of annual tree-ring widths as the
response. Explanatory variables are three 2-Level factors
(species,age,soil) and as continuous variables temperature,
precipitation and an element input into the ecosystem.

At the end I want to find out, if there is an effect on the tree-ring
width based on the interaction of the climate-data and the element input.

Best regards
Carsten



Eric Nord, Post Doctoral Scholar
Department of Horticulture
The Pennsylvania State University
222 Tyson Building, University Park, PA 16802
814-863-2313
ericnord@psu.edu

Get a bicycle. You will not regret it. If you live. - Mark Twain

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