# Average of Standard Deviation

How do I calculate the average standard deviation?

I have 27 standard deviations, each derived from 5 measurements per participant (27 participants), and calculated with SPSS. Do I simply take a mean of the SD's, or do I need to do something more advanced?

• If you want the average standard deviation, you need to compute the mean $\sum std_i\over 27$ – Furrane Jul 19 '17 at 8:12
• I thought it was this, thanks! – Chris Parker Jul 19 '17 at 8:18
• no problem, feel free to accept my answer to close the topic, or ask other questions you might have. – Furrane Jul 19 '17 at 9:17