at the moment I am struggling with calculating important parameters for my validation report...
Maybe you can help me out?

I am not sure if I have calculated the within-run/between run and relative error, correctly. For precision I have found a great tutorial: http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=0CC0QFjAB&url=http%3A%2F%2Fphysiologie.envt.fr%2Fspip%2FIMG%2Fdoc%2F7-_precision_CORR.doc&ei=4e4rVYDUH8LuaNn_gdgG&usg=AFQjCNESA1bWQybk5PvSGS8G2GWClg0EaA&bvm=bv.90491159,d.d2s

I am wondering if I can use the same technique to calculate the mean+/-SD and relative error?

Actual concentration: 10mg/l

Day 1 2 3
X 9.796 10.73 10.20
SD 0.54307 0.930897 0.556776
Variance 0.294925 0.866569 0.30999

In Excel for One-Way-ANOVA also the descriptives are calculated.
Is it right to use the Total mean+/-SD as the within-run mean+/-SD and within run corresponding relative error?
is it right to calculate a "new" mean (and the corresponding relative error) of the 3 means and use the between group mean square to calculate SD?

I was looking in the web to find a similar tutorium about this topic, unfortunately I had no luck. So if you know a easy tutorium (similar to the one above), please let me know.

Thank you in advance!