Re: st: RE: bihistogram

[Ronan Conroy <rconroy@rcsi.ie>]

On 27 Aug 2008, at 12:16, Rajesh Tharyan wrote:

> Hi sorry about the post with no link. Not sure what happened
>
> http://www.itl.nist.gov/div898/handbook/eda/section3/bihistog.htm

Looking at this, I am still not sure that this is the best way of  
displaying the data. For several reasons

1. Histogram shape is notoriously sensitive to the width and starting  
position of bins.
2. The eye is better at comparing side-by-side plots where position on  
the same scale is used to make the comparision
3. A histogram does not show the data
4. A histogram cannot be used to infer descriptive statistics

I would recommend, as an alternative, Nick Cox's -stripplot- with - 
vertical- and -box- options. Suddenly you see far more of the data,  
and are in a far better position to make comparisons.



Ronan Conroy
=================================

rconroy@rcsi.ie
Royal College of Surgeons in Ireland
Epidemiology Department,
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http://www.flickr.com/photos/ronanconroy/sets/72157601895416740/

P    Before printing, think about the environment




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