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AudreyM
Calcite | Level 5

i have to do this proc genmod:

PROC GENMOD DATA = _1;
  CLASS TRTP1-TRTP3 country1-country21 NEXTGR11-NEXTGR12 FEVPGR11-FEVPGR13;
  MODEL AVAL = TRTP1-TRTP3 country1-country21 NEXTGR11-NEXTGR12 FEVPGR11-FEVPGR13 /
  OFFSET=LNFUDUR2 DIST=negbin LINK=log;
  BAYES SEED=22022021 COEFFPRIOR=uniform THIN=100 OUTPOST= dataset2 NMC=100000;
RUN;

 

but unfortunately, i have the below error messages (all the covariates are binary 0/1 and the AVAL variable includes only integer values from 0 to 5. Only the OFFSET variable is a continuous variable)

AudreyM_0-1671449940332.png

 

The distribution of AVAL is the following:

AudreyM_1-1671450115242.png

 

my thought is that is due to the low variability of AVAL because in a lot of strata, the available values of AVAL are only 0.

 

But these are the data that i have so i cannot change them. i have tried to round the offset variable so have a fix number of digits but does not change the outcome.

 

Would you have any solution to resolve this?

 

Thanks

Audrey

 

 

1 REPLY 1
PaigeMiller
Diamond | Level 26

Hessian not positive definite often is a result of the model not fitting the data well. See https://communities.sas.com/t5/Statistical-Procedures/mixed-model-NOTE-Convergence-criteria-met-but-...

--
Paige Miller

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