Hi,
I'm working on a new cube and i need to create a measure : "Std Dev of Value"
Transformer just don't do that. How can i do this calculation using external rollup or something else please ?
Example of datas :
Month Country Value
201202 FRANCE 15
201202 USA 12
201203 BRAZIL 3
I would like to show for year 2012 : sqrt((1510)²+(1210)²+(310)²/3) = sqrt((25+4+49)/3) = sqrt(26)
Do you have an idea?
Thanks !
Topic

Re: Standard Deviation in PowerPlay Transformer
20120604T23:13:42ZThis is the accepted answer. This is the accepted answer.PowerPlay for Windows plots these lines at 1.5 standard deviations from the mean. An example can be found by looking at Great Outdoors.
Hope this online help helps:
StandardDeviation
Description
Returns the standard deviation of selected data items.
You can use standard deviation to measure the deviation or dispersal of values from the mean. A low standard deviation indicates that most values are distributed close to the mean, and a high standard deviation indicates that values are more spread out from the mean.
Example
If the average mark for an exam is 63, approximately sixtyeight percent of the scores fall within the one standard deviation and approximately ninetyfive percent of scores fall within two standard deviations of the average value. So if the standard deviation is 5, approximately sixtyeight percent of the group scored between 58 (635) and 68 (63+5). Approximately ninetyfive percent of the group scored between 53 63(2*5) and 73 63(2*5).
The following formula represents the standard deviation for a sample: √(∑(∑())2
Syntax
standarddeviation (numeric_exp)
Example
standarddeviation (Product Cost)
Returns the result: A value indicating the deviation between product costs and the average product cost.
Note 
Re: Standard Deviation in PowerPlay Transformer
20120605T15:28:35ZThis is the accepted answer. This is the accepted answer. Damien63
 20120605T06:57:40Z
Thanks for your reply but i can't insert this function into the measure calculation (unknonw function)
Where should i enter it ?
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