Hi,
I'm currently in the process of running a linear mixed model in SPSS. Our study design is a repeated measures crossover design with 20 participants, 4 conditions and 5 trials (no between factors). We also wanted to add sex as a covariate and we wanted to add participant ID as a random effect. Our syntax can be found below: MIXED RANKL BY ParticipantID Trial Time WITH Sex
/CRITERIA=DFMETHOD(SATTERTHWAITE) CIN(95) MXITER(100) MXSTEP(10) SCORING(1) SINGULAR(0.000000000001) HCONVERGE(0.00000001, RELATIVE) LCONVERGE(0, ABSOLUTE) PCONVERGE(0, ABSOLUTE)
/FIXED=Trial Time Sex Trial*Time Trial*Sex Time*Sex Trial*Time*Sex | SSTYPE(3)
/METHOD=REML
/RANDOM=ParticipantID | COVTYPE(VC)
/REPEATED=Trial*Time | SUBJECT(ParticipantID) COVTYPE(CS)
/EMMEANS=TABLES(Trial) COMPARE ADJ(LSD)
/EMMEANS=TABLES(Time) COMPARE ADJ(LSD)
/EMMEANS=TABLES(Trial*Time) .
Is this correct?
Nick
I think the syntax is ok, but do you have problem with "the final Hessian matrix is not positive"? Because i have a similar dataset, and i don't know if it is right to keep these results