# Re: st: scatter with aweight - consistent sizing across subsets of observations

 From Dan Weitzenfeld To statalist@hsphsun2.harvard.edu Subject Re: st: scatter with aweight - consistent sizing across subsets of observations Date Thu, 26 Mar 2009 10:52:00 -0700

```Thanks Friedrich - very helpful.  I searched the archives but didn't see that.

So if I understand correctly, Stata takes into account the range of
weights for all observations selected by the -if- group (and only
those selected by the -if- group), even if they lack a coordinate and
thus will not be plotted?

It seems a small step from that order of operations to one in which
the range of weights for all observations is taken into account, and
then only those selected by the -if- group are plotted.  But I'm sure
there's a reason it's the way it is.

On Thu, Mar 26, 2009 at 10:26 AM, Friedrich Huebler <fhuebler@gmail.com> wrote:
> Dan,
>
> You can find the solution to your problem in this post:
>
> http://www.stata.com/statalist/archive/2008-08/msg00987.html
>
> The example uses overlaid scatterplots but the principle applies to
> plots that are drawn separately. Try the code in the post and add one
> new command at the end:
>
> . twoway scatter y x [w=weight], by(group) name(D) legend(off)
>
> A more complicated example is shown here:
>
> http://www.stata.com/statalist/archive/2008-08/msg00982.html
>
> Friedrich
>
> On Thu, Mar 26, 2009 at 12:22 PM, Dan Weitzenfeld
> <dan.weitzenfeld@emsense.com> wrote:
>> Hi All,
>> I am confused as to how exactly Stata determines what will be the
>> largest and smallest marker size when using -scatter- with aweights.
>> My goal is to create a series of aweighted scatterplots, each one on a
>> subset of my data, with the relative marker sizing consistent across
>> plots.  That is, if a point in my first graph and a point in my second
>> graph are both weighted 100, I'd like them to be the same size,
>> regardless of what other points are plotted on each.
>>
>> My idea for how to do this is to create two fake datapoints, one equal
>> to the universal minimum and one equal to the universal maximum of the
>> weights, and to include these fake datapoints in each plot.  Since I
>> am copying the graphs into PowerPoint and ungrouping them anyway, I
>> can just delete these two fake points.
>>
>> Is there any reason this should not work?
>> Is there a simpler way?
>>
>> Dan
>
> *
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>

--
Dan Weitzenfeld
Media Analyst
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*
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```