Correlations > 1
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Correlations > 1

Does this mean no-one had any ideas about this in a whole week?

Time for a holiday -- Happy Easter :-)


>X-Authentication-Warning: petidomo set
sender to using -f
>Date: Mon, 10 Apr 2000 14:59:43 +1000
>From: Kim Bunter <>
>Subject: Correlations > 1
>Hi all,
>I have just done a series of bivariate analyses for 171 trait combinations.
>Incidentally, I was most impressed with how little 'fiddling' I had to do
>in ASREML to achieve convergence for the majority of these trait
>combinations - so I am getting more impressed by the day with ASREML :-).
>Anyway, it does leave me with a general query as to what one should do when
>a correlation (for example) goes just outside the parameter space? I prefer
>to do all my analyses in the land of no constraint - and even many highly
>correlated traits fell quite nicely into place within the parameter space,
>so this was generally not an issue. However, there are just a couple of
>trait combinations which would seem to benefit from using !GP or similar to
>constrain the estimates, but I don't see much point. For example, each time
>I have obtained an estimate >1 (eg. 1.003 or 1.01 - you can see they're not
>that wild, and could even be mistaken for a rounding error at the lowest
>level), the associated standard error would still indicate that the
>correlation was no different to unity anyway. I think I should just present
>them as is (against the common trend of not presenting estimates outside
>the parameter space?). I was wondering of the prevailing attitudes of
>others to this dilemma, or do you all tend to use constraints?? I hesitate
>to use constraints myself because of the potential to bias other estimates.
>So, I am looking forward to your ideas!
>Kim Bunter (M.Rur.Sc)
>PhD Student
>Animal Genetics and Breeding Unit
>University of New England
>Armidale, NSW, 2351
>Ph (ISD): -61-2-67733788
>Fax (ISD): -61-2-67733266
>Asreml mailinglist archive:
Kim Bunter (M.Rur.Sc)
PhD Student
Animal Genetics and Breeding Unit
University of New England
Armidale, NSW, 2351

Ph (ISD): -61-2-67733788
Fax (ISD): -61-2-67733266
Asreml mailinglist archive: