You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@jmeter.apache.org by bu...@apache.org on 2017/05/27 22:47:19 UTC
[Bug 61130] New: Percentile and Median : Document algorithms used
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
Bug ID: 61130
Summary: Percentile and Median : Document algorithms used
Product: JMeter
Version: 3.2
Hardware: All
OS: All
Status: NEW
Severity: enhancement
Priority: P2
Component: Main
Assignee: issues@jmeter.apache.org
Reporter: p.mouawad@ubik-ingenierie.com
Target Milestone: ---
Issue related to Bug 61071 and Bug 61078
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
--- Comment #3 from Aleksei Balan <ab...@gmail.com> ---
Hello Apache community.
I use JMeter almost every day and attach its data to my reports.
That is why I care about accurate results so much.
The median is calculating incorrectly. It is not corresponding to wikipedia
example.
https://en.wikipedia.org/wiki/Median (example at the top right corner of the
page)
The percentile is calculating incorrectly. It is not corresponding to wikipedia
example.
https://en.wikipedia.org/wiki/Percentile (Example 3)
To help with the fixes I provided pull requests for both of them.
And now you are discussing is it a bug or a feature and wondering should
something be changed or not.
All right then.
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
Philippe Mouawad <p....@ubik-ingenierie.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |abalanonline@gmail.com
--- Comment #1 from Philippe Mouawad <p....@ubik-ingenierie.com> ---
*** Bug 61071 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
Felix Schumacher <fe...@internetallee.de> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |ajay.singhes@gmail.com
--- Comment #8 from Felix Schumacher <fe...@internetallee.de> ---
*** Bug 61725 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
--- Comment #6 from Philippe Mouawad <p....@ubik-ingenierie.com> ---
*** Bug 61071 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
--- Comment #5 from Philippe Mouawad <p....@ubik-ingenierie.com> ---
*** Bug 61078 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
--- Comment #2 from Philippe Mouawad <p....@ubik-ingenierie.com> ---
*** Bug 61078 has been marked as a duplicate of this bug. ***
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
--- Comment #7 from Aleksei Balan <ab...@gmail.com> ---
Hello Apache community,
Can you please review these two pull requests
https://github.com/apache/jmeter/pull/295
https://github.com/apache/jmeter/pull/296
They are fixing some calculation defects. I understand that these errors
affect the results very rarely (especially on big number of samples)
but still I think it is a good idea to have more precise calculations.
Thank you.
Aleksei Balan
--
You are receiving this mail because:
You are the assignee for the bug.
[Bug 61130] Percentile and Median : Document algorithms used
Posted by bu...@apache.org.
https://bz.apache.org/bugzilla/show_bug.cgi?id=61130
Philippe Mouawad <p....@ubik-ingenierie.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |p.mouawad@ubik-ingenierie.c
| |om
--- Comment #4 from Philippe Mouawad <p....@ubik-ingenierie.com> ---
Hello Aleksei,
I didn't want to be rude by closing issue.
First thanks for your time, your PR and work.
I closed the PR for the following reasons:
- My understanding is that on large set of data which should be the case for
correctly ran tests, the different percentiles algorithm will lead to similar
values. "There is no standard definition of percentile,[2][3][4] however all
definitions yield similar results when the number of observations is very large
and the probability distribution is continuous"
- As per Felix note, there doesn't seem to be 1 truth
- Changing the algorithm might lead to changes in results that will trigger
potentially a lot of "false" issues.
Still maybe there is a better way of fixing the issue, SO I reopened the bugs.
It appears to me we could fix median as per your PR and use Math Percentile
setup with R_1 accross all JMeter library.
But I won't touch them myself as I have no firm opinion.
Thank you
--
You are receiving this mail because:
You are the assignee for the bug.