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]

Re: st: Dirifit / ddirifit: "maximum number of iterations exceeded"


From   Mark Nichols <nichols.mark0@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: Dirifit / ddirifit: "maximum number of iterations exceeded"
Date   Sat, 24 Apr 2010 22:37:47 -0700

dirifit is one of those things that sounds good in theory but fails
miserably in practice - as you found out. It reminds me of count
models that people no longer pay much attention to. I'd suggest you
try linear models (ols). Once that's working, you can still try
dirifit, at which point you might conclude that it doesn't make a
meaningful contribution and will only confuse the reviewers.

Regards,

Mark


> my coauthor and I are trying to use dirifit to analyze patterns of
> cross-citations between different courts. In order to do so, we have
> transformed our dataset into a matrix showing what percentage of each
> courts' citations points to a particular other court.
>
> Depending on which control variables we use, we sometimes do not get results
> at all (dirifit reports non-converging iterations until the user stops it).
> Sometimes, when we do get a result with dirifit, ddirifit will result in an
> error message saying "maximum number of iterations exceeded" (I typically
> set the maximum number up to 10000). We suspect that one of the problems
> could be that we have many values in the matrix that are very close to zero.
*
*   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