[Fwd: Problem with ASREML list]
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[Fwd: Problem with ASREML list]


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The appended message just got bounced by the ASREML list.   Any chance you
could help me to send it to a good home?


        I am trying to choose the number of knot points for splines, and
getting some unexpected results.

        I proceed as follows.   I specify a low number of knot points (say
4) using the qualifier

!spline 4

in the data file specification in the .as file.   I then write a .pin file
and generate a .pvs file.   This contains 4 values for each fitted curve, as

        However, if I specify a higher number of knot points (say 10), the
number of fitted values per curve is one or two less than the number specified.

        The manual cautiously states that the qualifier !SPLPOINTS s affects
the number of distinct points recotnised by the spl(.) model function - not
that s is the actual number of knots.   Also, the qualifier given in the
manual is !SPLPOINTS, whereas I am using !spline - I think I got the latter
direct from Arthur.   Are they equivalent?   (I can't find anything about
!spline in the manual.)

        Do I just have to get the precise number of knot points that ASREML
has chosen from the output?

Nick Galwey
N.W. Galwey,
Faculty of Agriculture,
University of Western Australia,
Nedlands, WA 6709, Australia.

Tel.: +61 9 380 1959 (direct line)
      +61 9 380 2554 (switchboard)
Fax:  +61 9 380 1108
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