Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down on April 23, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

st: Non-reported s.e. for kappa


From   "Karen Wright" <Karen.Wright@icr.ac.uk>
To   <statalist@hsphsun2.harvard.edu>
Subject   st: Non-reported s.e. for kappa
Date   Wed, 14 Apr 2010 15:38:18 +0100

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)

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



The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company Limited by Guarantee, Registered in England under Company No. 534147 with its Registered Office at 123 Old Brompton Road, London SW7 3RP.

This e-mail message is confidential and for use by the addressee only.  If the message is received by anyone other than the addressee, please return the message to the sender by replying to it and then delete the message from your computer and network.

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index