Normal Distribution Formula

[#1]

HI all,

currently i am using standard deviation formula and giving a user to flex SD i.e 1,2,3:

stdev(aggr(sum(qty),date,stockid)*SD where SD is a variable and default value is 2. thus user can amend in dashboard based on its requirement

now user wants to input probability i.e 60 or 70 or 80 percent.. what function i should use in above formula, so that when user inputs value in a variable as 95%, the variable should translate the input value to derive value as 2, to get 2 standard deviation

like for example in excel NORMSINV function will convert probability into SD i.e NORMSINV(60%+(1-60%)/2) gives 0.8416 standard deviation

thanks in advance
Sukhwant

[Gysbert_Wassenaar]

Sounds like you're looking for the norminv function.

[#3 · Accepted solution]

As Gysbert told, norminv() is what you need.

=NORMINV(0.8,0,1) is equivalent of excell NORMSINV (0.8) and gives exactly result you need.

You may also use other than in normal distribution values for mean and SD.