statistics
 

Hi everyone,

For qPCR we do 3 technical replicates and 3 biological replicates. This generates means and SDs for the technical replicates. The biological replicates are the mean of the technical replicates' means. So how do I calculate SD/SEM for the biological replicates? I've seen a lot of people ignore the SD of the technical replicates and calculate SD for the biological replicates. Surely it should be SEM as it's the mean of means?

Any help would be much appreciated.
Cat.