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Re: st: Problem with xtmixed
Noori Akhtar-Danesh <[email protected]> is having difficulty getting
-xtmixed- to match -xtreg- and -gllamm-. When running -xtmixed-, Noori
types the following:
. xtmixed birwt male ... pretri2 pretri3 || momid, mle
and the resulting estimation is having difficulty converging. Noori has
simply omitted the colon after the group identifier -momid-, causing
-xtmixed- to interpret the above as
. xtmixed birwt male ... pretri2 pretri3 || _all: momid, mle
an entirely different (and somewhat nonsensical in this case) model, hence
the failure to converge.
Typing
. xtmixed birwt male ... pretri2 pretri3 || momid:, mle
(with the colon after -momid-) will achieve the desired result.
Noori is not the first to be bit by this insidious bit of syntax. The
original intent of providing a shortcut has proven in this case to not to be
worth the confusion it may cause. As such, a future version of -xtmixed-
will require explicit specification of the level group identifier with the
colon, and issue a syntax error otherwise.
--Bobby
[email protected]
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