At 06:54 PM 12/1/2003, you wrote:
>Greetings STATAlisters -
>The query that follows may have a straightforward response,
>however, I'm at a loss for a solution so I'm posing the
>question here. Suppose I have three variables and I generate a
>Venn diagram to assess overlap, is there a way to quantify the
>overlap (aside from the percent returned by the Venn Diagram)
>and/or run a statistical test on the overlap? My colleague
>suggested the kappa statistic as a means for quantifying the
>overlap but I disagree since kappa measures agreement - can
>anyone suggest an alternative and/or confirm my colleague's
>suggestion?
>Many Thanks,
>Clint Thompson
Overlap IS agreement in a certain sense.
A statistical test testing what hypothesis? The kappa would be perfectly
valid in testing one such hypothesis, namely that the overlap is what would
be expected by chance (allowing for different catchment or inclusion
probabilities for each of the three variables). It is difficult to say
without knowing specifics (what the variables are, what interests you about
the overlap, etc).
The documents accompanying this transmission may contain confidential
health or business information. This information is intended for the use of
the individual or entity named above. If you have received this information
in error, please notify the sender immediately and arrange for the return
or destruction of these documents.
________________________________________________________________
Constantine Daskalakis, ScD
Assistant Professor,
Biostatistics Section, Thomas Jefferson University,
211 S. 9th St. #602, Philadelphia, PA 19107
Tel: 215-955-5695
Fax: 215-503-3804
Email: [email protected]
Webpage: http://www.jefferson.edu/medicine/pharmacology/bio/
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
