Question about Alscal ("Fixed" option)

[Luigi Curini (luigi.curini)]

Dear all,
I have a question about the Alscal procedure in Spss 15. I'd like to force Alscal to use an externally defined structure without modification to calculate the best values for all unfixed portions of the
structure. Now, following the Spss manual, I added in the Synthax the following line  /FILE=ONE CON(FIXED) (indeed, I'm interested in fixing the column stimulus coordinates using the SHAPE= RECTANGULAR assumption). The Alscal procedure works fine, the only problem is that instead of reading the stimulus coordinates as fixed values, as they should be, the procedure reads them like they were initial values. Indeed, regardless of writing  /FILE=ONE CON(FIXED) or /FILE=ONE CON(INITIAL) in the Synthax, in both case the Alscal procedure treats the external configuration as initial coordinates that must be modified during each iteration. Is there anyone who was successful in using the CON(FIXED) option? Or is there a bug in the program?
Thank you very much,
Best,
Luigi

[Kooij, A.J. van der]

 

________________________________

From: Busing, Frank
Sent: Sun 20/05/2007 15:43
To: Kooij, A.J. van der
Subject: RE: Question about Alscal ("Fixed" option)


Dear Luigi.
 
Probably.
But why don't you use PREFSCAL.
It has a superior algorithm for the rectangular data
and is able to fix coordinates,
as you wish.
Check it out!
 
Regards, Frank.
 
-----------------------------------------------
 Frank M.T.A. Busing
 Psychometrics and Research Methodology
 Leiden University
 P.O.Box 9555, 2300 RB Leiden, The Netherlands
-----------------------------------------------

________________________________

From: Kooij, A.J. van der
Sent: Thu 5/17/2007 21:23
To: Busing, Frank
Subject: FW: Question about Alscal ("Fixed" option)


 

________________________________

From: SPSSX(r) Discussion on behalf of Luigi Curini (luigi.curini)
Sent: Thu 17/05/2007 18:08
To: [hidden email]
Subject: Question about Alscal ("Fixed" option)



Dear all,
I have a question about the Alscal procedure in Spss 15. I'd like to force Alscal to use an externally defined structure without modification to calculate the best values for all unfixed portions of the
structure. Now, following the Spss manual, I added in the Synthax the following line  /FILE=ONE CON(FIXED) (indeed, I'm interested in fixing the column stimulus coordinates using the SHAPE= RECTANGULAR assumption). The Alscal procedure works fine, the only problem is that instead of reading the stimulus coordinates as fixed values, as they should be, the procedure reads them like they were initial values. Indeed, regardless of writing  /FILE=ONE CON(FIXED) or /FILE=ONE CON(INITIAL) in the Synthax, in both case the Alscal procedure treats the external configuration as initial coordinates that must be modified during each iteration. Is there anyone who was successful in using the CON(FIXED) option? Or is there a bug in the program?
Thank you very much,
Best,
Luigi



**********************************************************************
This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom they
are addressed. If you have received this email in error please notify
the system manager.
**********************************************************************