Hi everyone. What you see here is er fourier spectra. If i want to conclude that there is a statistical significance difference between the peak value around 30 hz, and all the other smaller peaks. Should i do as following. Estimate the mean value as 2. Estimate the mean peak value to around 3. And last estimate the mean lowest peak value as 1. Then calculate the standard deriviation to 1,225. And after that, i could calculate 5 times sigma to 6,124. And because the peak value is around 13, and therefore is bigger than 6,124. I can conclude with 99,97% certainty, that there is a significance difference between the peak value and the other peak values. Is it right, what i'm doing here?