Re: SPSS Syntax MIXED Model

Posted by Alex Reutter on
URL: http://spssx-discussion.165.s1.nabble.com/SPSS-Syntax-MIXED-Model-tp5713934p5713960.html

Typically, I think a random coefficient model will look like:

MIXED
 
Blood_test_Value BY Gender Ethnicity WITH Age
 /FIXED =
Gender Ethnicity Age | SSTYPE(3)
 /METHOD = REML
 /RANDOM INTERCEPT Age | SUBJECT(id) COVTYPE(UNR) .


See, for example, Model 5 at http://publib.boulder.ibm.com/infocenter/spssstat/v20r0m0/topic/com.ibm.spss.statistics.help/syn_mixed_examples.htm.  I don't think the REPEATED statement belongs; the random slope should be modeled as part of the RANDOM subcommand.

Alex




From:        Zalihe <[hidden email]>
To:        [hidden email]
Date:        07/01/2012 08:03 PM
Subject:        SPSS Syntax MIXED Model
Sent by:        "SPSSX(r) Discussion" <[hidden email]>




I just wanted to ask something about the SPSS problem i am trying to solve.

I have repeated measures of a blood test for each patient (2-15 measurements
per patient) and i want to find out the effect of each independent variables
such as age, gender and ethnicity on the decline of this blood test over
time. Therefore i am trying to run a random intercept and random slope
models on repeated measurements by using MIXED model procedure in SPSS.
However, the program is giving me an error of saying that there is
insufficient memory to estimate model parameters. Totally i have 135823
cases of rows. When i tried to run in a smaller size of cases, the code did
worked. What can i do to solve my problem ? Is it a problem due to computer
memory or SPSS memory ? How can i make the code work ?

My code is something like;

MIXED Blood_test_Value BY Gender Ethnicity WITH Age
 /CRITERIA=CIN(95) MXITER(100) MXSTEP(5) SCORING(1)
SINGULAR(0.000000000001) HCONVERGE(0,
   ABSOLUTE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0.000001, ABSOLUTE)
 /FIXED=Gender Ethnicity Age | SSTYPE(3)
 /METHOD=ML
 /PRINT=G  SOLUTION TESTCOV
 /RANDOM= INTERCEPT | SUBJECT(ID) COVTYPE(ID)
/REPEATED= Time_point  | SUBJECT(ID) COVTYPE(UNR).

Thank you.
Zalihe.