7 Replies Latest reply on Mar 12, 2018 2:12 PM by Johnny Hass

How to identify the outliers in a distribution using standard deviation?

Hi,

I am attaching a list of customers and their cost . each customer is categorized . also each customer has a type of connection . I want standard deviation for that set. i also like to identify the outliers based on their cost using 1 standard deviation form the mean. i need a field that says whether the customer is an outlier or no based on their cost.I like to add that field to the filter and be able to filter on whether each customer is an outlier or no.

I tried so many ways, first i calculated the standard deviation for the set and then and i calculated the average for the set and can't find a way.

any help is appreciated.

• 1. Re: How to identify the outliers in a distribution using standard deviation?

Hi Tony Fahd Did you try a calculated field as such?  If [Std. Dev of client] > [Std. Dev of Category] then 1 else 0 end.  You could then put this on the filter shelf, or even on the color shelf instead, so as to see both together.  I didn't see calculated fields for std. dev. in your workbook.  This is what I would try.  Let me know if this helps

Matthew

• 2. Re: How to identify the outliers in a distribution using standard deviation?

Thanks Matthew. I calculated two standard deviations using the customer and category.

{INCLUDE [Category]:STDEV([Cost])}

{INCLUDE [customer]:STDEV([Cost])}

is this the way you would calculate the std deviation for each set?

and then used the if function but it's not working. any suggestion?

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• 3. Re: How to identify the outliers in a distribution using standard deviation?

Tony Fahd See attached.  I think I got it figured out.  You'll need 10.4.  Let me know if this worked...

Matthew

• 4. Re: How to identify the outliers in a distribution using standard deviation?

this is great. the only issue I have since it's fixed standard deviation, the standard deviation is not changing when I change the Type. I used the type as filter but std dev is not changing when I include/exclude some types

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• 5. Re: How to identify the outliers in a distribution using standard deviation?

Matthew

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• 6. Re: How to identify the outliers in a distribution using standard deviation?

Thanks!!

• 7. Re: How to identify the outliers in a distribution using standard deviation?

This is really great!  Thanks for posting.

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