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

[Mark Nichols <nichols.mark0@gmail.com>]

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.
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