[R] repeated measurements with R

Nicolaas Busscher nbusscher at gmx.de
Tue Jan 20 18:04:03 CET 2004


Hello All,
I have a more statistical question, and how this is implemented in R.

The problem is the following:
We have 2 different solutions (samples), which are filtered and then
the concentration of the filtrate is measured.

We want to evaluate how the filter proces and the concentration
measurement influences the detection of the difference of the two
solutions and which step has which influence. So we filter the 2
solutions each 6 times and get 12 filterd solutions. each of this
filtrate is measured 8 times, so we get 12 *8 96 conc. values. i get a
data table of:

solution nr.filter nr.measures conc.
1 or 2    1 till 6  1-till 8    96 values
because the concentrations are "repeated measurements" as i was told
by a statistician (i am not) it is not allowed to make a anova with
the formula: conc~solution+nr.filter+nr.measures.

my question is: 
how can i solve this in R?

thanks
Nicolaas Busscher

-- 
Dr.Nicolaas Busscher Universität GH Kassel
Nordbahnhofstrasse: 1a, D-37213 Witzenhausen
Phone: 0049-(0)5542-98-1715, Fax: 0049-(0)5542-98-1713




More information about the R-help mailing list