topic Re: Help with Standard deviation Full population Not a sample in QlikView

Help with Standard deviation Full population Not a sample

Fri, 11 Oct 2013 22:53:51 GMT

Hello

I'm want to calculate STDEV and when i use STDEV Function and it calc like this

values	avg	stdev
600
700
	650	70.71068

and it suppose to be 50

in excel there is STDEV.P which calc 50

which func. is the correct one ?

thanks

zvi

Re: Help with Standard deviation Full population Not a sample

swuehl — Fri, 11 Oct 2013 23:53:46 GMT

The difference between the two functions ist just a factor sqrt( n / (n-1) )

You got two values in your population, n=2, factor= sqrt(2)

http://office.microsoft.com/en-001/excel-help/stdev-HP005209277.aspx

Re: Help with Standard deviation Full population Not a sample

Sat, 12 Oct 2013 00:57:49 GMT

Helo Zvi;

The function "STDEV" QlikView is equivalent to the "STDEV.A" in excel, not "STDEV.P" to use this function in excel will bring the same value displayed for you.

Re: Help with Standard deviation Full population Not a sample

Sat, 12 Oct 2013 08:23:49 GMT

in excel the STDEV.A give me the same Result as STDEV

but if i calculate by my self with the full formula

the result is the same as STDEV.P

and its 50 which is the correct result

(values:600, 700 , avg=650, STDEV Shuldbe 50 )

is there any way to use a function for stdev which will give me 50 instead of 70.71

this is the formula for STDEV .

thanks

zvi

Re: Help with Standard deviation Full population Not a sample

swuehl — Sat, 12 Oct 2013 08:30:18 GMT

My previous post is still in moderation.

Basically, you need to correct stdev with a factor:

The difference between the two functions ist just a factor sqrt( n / (n-1) ) You got two values in your population, n=2, factor= sqrt(2)

stdev = factor * stdev_p

Re: Help with Standard deviation Full population Not a sample

Sat, 12 Oct 2013 10:10:41 GMT

thank you it work

the factor for n=2 is sqrt(2)

factor for n=10 is sqrt(10/9).....

and need to divide...

it works..

thank you

Re: Help with Standard deviation Full population Not a sample

jansen28 — Fri, 17 Oct 2014 07:37:41 GMT

It was very helpful and thank