calculating the weighted Median in SPSS

[Philipp Nowotny]

Hi everybody!

We would like to know how to calculate the weighted Median with SPSS! It
seems to be a simple question, but in fact it`s not! Books or several
mathematicians of different branches couldn`t help. But as SPSS offers this
task, there must be a way to calculate it! Can anybody tell me something
about the formula behind?

Thanks,

Sabine Fischer, Philipp Nowotny

[Richard Ulrich]

On Fri, 01 Oct 2004 12:31:46 GMT, "Philipp Nowotny"
<philipp...@manova.at> wrote:

> Hi everybody!
>
> We would like to know how to calculate the weighted Median with SPSS! It
> seems to be a simple question, but in fact it`s not! Books or several
> mathematicians of different branches couldn`t help. But as SPSS offers this
> task, there must be a way to calculate it! Can anybody tell me something
> about the formula behind?

Googling shows me a couple of different ideas, maybe, of what
a "weighted median" is.

Here is the simpler explanation, which is probably what
you refer to in SPSS -
http://www.fabalou.com/Access/Modules/recordset_weighted_median.asp

Effectively -
For an even number of points, with ties above and below
the median value, this shows how to split the range
proportionate to the Ns.

You could probably find out for sure what SPSS is doing
by logging in to the SPSS online site and finding Algorithms
for the particular procedure. (user "guest", password "guest")

I'm not sure if this is different in result, but here is an
explanation which is certainly more theoretical and difficult -
http://sepwww.stanford.edu/public/docs/sep92/jon3/paper_html/node2.html

--
Rich Ulrich, wpi...@pitt.edu
http://www.pitt.edu/~wpilib/index.html