I am analyzing my results for a high-school biology paper. My data set consists of 20 groups in total, each having 4 repeats, so each is a small sample. I have a few (4) outliers that have a value lower than the control group (which is practically impossible and thus certainly the effect of a technical error).
Can I exclude the outliers when calculating the mean value or standard deviation, as they largely affect both parameters?
I am quite green when it comes to statistics, so I would hugely appreciate your help. Many thanks!