Hi volunteer statisticians,
I want to combine the stdev of 6 populations of means for two different
treatments and there seem to be many methods for doing so.
It is QPCR data consisting of 3 technical replicates building one mean
and 6 biological samples in two treatment groups. Now as an overview I
just assumed each value to be a replicate it self within each of the two
treatments and calculated an overall mean with overall stdev. But this
seems to be a bit of a mistake. Is it?
First - I think I need a more robust mean. So I applied the geometric
mean. Next I combined the deviations by calculating with the formula for
error propagation (wiki german "Fehlerfortpflanzung"). Isn't this
a too
complicated way?
So:
3 technical replicates build one mean with stdev
6 of these build the population of one treatment
2 treatments....
Any suggestions which method I should use and how I perform the
calculations?
Thanks for your help
Best Holger
