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How to Calculation Standard Deviation of the Numbers
Asked by riskosoft on September 25, 2014 at 07:46 PMI need to use the calculate form and use the standard deviation for my work.
Can you explain to me how i can make it ?

JotForm Support
Hi,
We do not have direct solution for this but let me check and verify it first if the calculation wizard is capable to handle standard deviation.
Stay tuned for updates. Thanks!

JotForm Support
Looks like it's possible but it requires few calculation widgets to get it done.
Kindly check and clone this form so you can see the hidden calculation fields and formulas.
http://form.jotformpro.com/form/42680933363963?
Try it with 2 and 3 numbers and compare the results. I am using this calculator: http://www.mathsisfun.com/data/standarddeviationcalculator.html
Hope this helps!

Thank you for your message, but i have a différent Result with EXCEL
Look i have calculate the standard deviation with EXCEL and When i look your FORM the result is Different, What do you think ?

I'm still trying to understand the formula of STDEV so I'm not sure which is the correct one. Can you please show the sample formula in your Excel so we test using the calculation wizard.
Here's how I understand the formula.
Number 1 + Number 2 / 2
Number 1  2 (mean)
Number 2  2 (mean)
Diff of num 1  2 Squared + Diff of num 2  2 Squared
Calculate the standard deviation:
Sum of Squared 1 + Squared 2 / mean  1
Here is my reference http://standarddeviation.appspot.com/.

I used an online calculator to compute for STDEV and it seems the formula created by my colleague Elton is fine. Please try inputting a number here http://easycalculation.com/statistics/standarddeviation.php.