[Rasch] Negative pt-bis and fit of 1.0? How can this be?

Mark Moulton markhmoulton at gmail.com
Wed Mar 7 10:05:51 EST 2012


Cool!  See you in Vancouver.

On Tue, Mar 6, 2012 at 1:53 PM, Stuart Luppescu <slu at ccsr.uchicago.edu>wrote:

> On Tue, 2012-03-06 at 15:36 -0600, Stuart Luppescu wrote:
> > Are you saying that if I just generated 1's and 0's randomly and tried
> > to calibrate them they would all fit? Hmmm. I'm going to have to try
> > that....
>
> Very interesting, indeed! Of course, you get 0 reliability and
> point-biserials near 0, but all the fit statistics are very close to
> 1.0! Mark Moulton gets a beer next time I see him for providing the
> instructional moment of the day.
>
> --
> Stuart Luppescu -=- slu .at. ccsr.uchicago.edu
> University of Chicago -=- CCSR
> 才文と智奈美の父 -=-    Kernel 3.2.1-gentoo-r2
> Trevor Hastie: It would be great to have a
>  'clickable' digest, where the topics list is a set
>  of pointers, and clicking on a topic takes you to
>  that entry. Jeff Gentry: I sincerely hope you
>  don't mean that you wish HTML enabled content in
>  the actual emails coming through the mailing list.
>  People who send HTML in email text should be taken
>  out back and shot :) Peter Dalgaard: Pretty much
>  what my spam filter does... Well, it kills the
>
> _______________________________________________
> Rasch mailing list
> Rasch at acer.edu.au
> Unsubscribe:
> https://mailinglist.acer.edu.au/mailman/options/rasch/markm%40eddata.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://mailinglist.acer.edu.au/pipermail/rasch/attachments/20120306/25307857/attachment.html 


More information about the Rasch mailing list