Re: st: RE: Adding normal density to overlayed histograms

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Thu, 21/10/10, Nick Cox wrote:
> -5. If the normal is a reference, the comparison is of a
> curve with a set of bars, which is not the easiest
> comparison to get right. (Sometimes, the graph is a
> propaganda graph presented in the spirit "Look, it's roughly
> normal", when a more critical look would show important
> features, such as heavier tails or a mild outlier.)  

I agree with Nick that quantile-quantile plots are a good 
alterantive, especialy if you want to plot multiple variables
in one graph.

Another alternative graph that is specifically designed for 
solving the 5th minus point of a histogram with an overlaid
normal curve is the hanging rootogram and suspended rootogram.
These are explained here:
<http://www.maartenbuis.nl/software/hangroot.html>

These graphs can be drawn with the -hangroot- package which can 
installed by typing in Stata -ssc install hangroot-. 

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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