Re: how to identify outliers

Im asking how to get the ones that dont fall near the avg.... so for
example lets say i have the following distances:
10,11,12,11,10,9,9,10,11,12,10,11,99

then 99 would be an outlier. the avg would be like 16 or 17 i reckon
with the 99. so i want a way to find aan outlier, remove it and then
recalcuate the avg...and then i'd get a 'better' avg.....

i did some seraching about outliers and most of hits are about R or
spss or some other statistical package.....so looking for a way to do
it wholly in pgsql.


Rhys

On Tue, Oct 27, 2009 at 4:53 PM, Ben Chobot <bench@silentmedia.com> wrote:
> Are you asking how to find the average and standard deviation? Or how to
> compare the your data against some set values? Perhaps an example would be
> appropriate; it's not very clear to me what you're asking.
>
> Rhys A.D. Stewart wrote:
>>
>> Hey all,
>> I have the following table:  data(pnum text, distance float8, route text).
>> I would like to remove the outliers in distance, i.e. lets say i get
>> the avg dist of pnum for each route and the std deviation of the
>> distance what is the best way to identify the outliers?
>>
>>
>> Rhys.
>>
>>
>