st: AW: Non-reported s.e. for kappa

["Martin Weiss" <martin.weiss1@gmx.de>]

<> 

You do not need an imaginary dataset, as the official example does not
return the se, either:


*************
webuse p615, clear
kap cat*
ret li
*************

The help file could make this fact clear, I think. BTW, a command reporting
a whole table inevitably runs into the problem which statistics it should
return. Just see what -summ- with a -varlist- hands back: The statistics for
the last variable in that -varlist-. The alternative would be to return a
-matrix-, of course...


HTH
Martin


-----Ursprüngliche Nachricht-----
Von: owner-statalist@hsphsun2.harvard.edu
[mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von Karen Wright
Gesendet: Mittwoch, 14. April 2010 16:38
An: statalist@hsphsun2.harvard.edu
Betreff: st: Non-reported s.e. for kappa

Dear All,
I have been working with kappa statistics and I have come across a
peculiarity that I don't fully understand.  Searching the help files and the
statalist archive did not shed any light on the matter unfortunately.
After running a simple composite kappa on multiple readers (3 categories)  I
then type -di r(se)- and obtain nothing!  The results have not been cleared
from memory as typing -di r(kappa)- displays the kappa value.  Does anyone
know why this is?
I am aware that test statistics cannot be calculated when the number of
ratings per subject vary.  Is there something similar happening here?!

I have shown below a snippet of the data and the commands used.  Snippet of
data contains the diagnosis (=1,2, or 3) for 6 readers (id2-id10) on 5
cases.  [Done using Stata10 on Windows.]

Thank you for taking the time to read this,
Karen

*************************************************
version 10.0

input case id2 id3 id6 id8 id9 id10
1 3 3 3 3 3 3
2 1 1 1 1 1 1
3 2 2 1 3 1 1
4 3 3 3 3 3 3
5 1 1 1 1 1 1
end

kap id*
di r(se)
di r(kappa)

*************************************************



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