BookmarkSubscribeRSS Feed
Miracle
Barite | Level 11
Hi everyone.

May I please ask what this " Convergence criteria met but final
hessian is not positive definite" outputed by proc mixed means?

my code is
proc mixed data=temp;
class Subject factory;
model log_exp = / solution;
random int / subject=Subject solution;
random int / subject=factory solution;
random int / subject=factory *Subject solution;
run;

Many thanks in advance.
1 REPLY 1
sfleming
Calcite | Level 5
Usually, this means the calculations came up with a negative value for one of the variance components. Take a look at the Covariance Parameter Estimates, and you should see one set to 0. You may need to adjust your model accordingly to avoid this situation.

sas-innovate-2024.png

Available on demand!

Missed SAS Innovate Las Vegas? Watch all the action for free! View the keynotes, general sessions and 22 breakouts on demand.

 

Register now!

What is ANOVA?

ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.

Find more tutorials on the SAS Users YouTube channel.

Discussion stats
  • 1 reply
  • 1244 views
  • 0 likes
  • 2 in conversation