# [rrd-users] Re: Median calculations ?

Alex Prinsier aphex at aphexer.dyndns.org
Tue Mar 14 18:27:17 MET 2006

```No it's not the same. Consider these numbers: {50,1,2,3,4}. The average
(50th percentile I believe is the same as average) = (50+1+2+3+4)/5 = 12.

The median however is the element in the middle which is 2. You can see
the clearly differ alot. The median is usually preferred above the
average when you expect to have extreme values (like the 50) and you
don't want to weigh them as much.

When you have an even amount of numbers the median is the average of the
2 middle numbers.

Alex

Alex van den Bogaerdt wrote:
> On Tue, Mar 14, 2006 at 04:47:08PM +0100, Ralf Kruedewagen wrote:
>> Hi,
>>
>> is there any chance to calculate the median with rrdtool ?
>
> Isn't this the same as a 50th percentile calculation? If so,
> this would be possible.
>

--
Unsubscribe mailto:rrd-users-request at list.ee.ethz.ch?subject=unsubscribe
Help        mailto:rrd-users-request at list.ee.ethz.ch?subject=help
Archive     http://lists.ee.ethz.ch/rrd-users