Possibility to avoid certain values which are way too deviant while calculating threshold

[Anders Håål]

Hi Rahul,
Its possible, but the question is what algorithm to use. The second 
question would also be what would you do with the remaining set, 
calculate a mean?
When it comes to exclude a deviant value it sound close to what is 
called a outlier, http://en.wikipedia.org/wiki/Outlier. There are a 
number of mathematical solutions to this problem, but not sure which 
would be applicable or correct. Check this link for a discussions on the 
topic where one approach is using standard deviation, but from the 
discussion it does not sound like a statistical correct approach.

If you or anyone else on this list find an good approach, I more then 
happy to try it. In Bischeck its possible to plug in your own functions 
as described in 
http://www.bischeck.org/wp-content/uploads/2014/06/Bischeck_installation_and_administration_guide.html#toc-Section-6.2 
so you can easily do your own testing. Using the cache browser cli 
http://www.bischeck.org/wp-content/uploads/2014/06/Bischeck_installation_and_administration_guide.html#toc-Section-4.4 
you can easily test your function.

Anders


On 12/17/2014 03:40 PM, Rahul Amaram wrote:
> Hi,
>
> I had a quick question. Let us say we calculate the threshold based on 
> the values of the past six days, one value per day. Now let us say, 
> out of 6 values, one of these values is way too deviant. Then is it 
> possible to exclude this deviant value from calculating the threshold?
>
> Thanks,
> Rahul.


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