Hi.
A warning.
It would appear that there was more than on bug infesting
the probit function (not link)in WinBUGS1.1 because one
seems to still be lurking in WinBUGS1.2beta, despite the
authors' claim to have fixed the probit function. Even
though the elements of my doodle specify that probit be
used as a function, when you get Doodle to write the code
it is specified as a link thus inverting the modeller's
intention. Thus logical node x with identity link and value
specified to probit(p) appears in the written code as
probit(x)<-p. Not what was intended. When sampled the node
returns the value specified by the written code not the
doodle.
Just so long as people are aware of the bug it should
not be a problem. But since the function is returning the
wrong value it is more dangerous than the old simple crash
(did I ever think that I would yearn for those
incomprehensible crashes!)
Good luck to all (hey it's still a good product and still
only beta)
Brian.
----------------------
Brian McArdle
[log in to unmask]
(64)9 3737599 X5845
Fax (64)9 3737018
Department of Statistics
University of Auckland
Private Bag 92019
Auckland
New Zealand
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