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05-14-2017 06:27 AM - edited 05-14-2017 06:29 AM

Hi all,

I am trying to do logistic regression with random effiect for binary data by GLIMMIX.

However, I get warinig message as follows;

WARNING: Obtaining minimum variance quadratic unbiased estimates as starting values for the covariance parameters failed

Anyone know how I can overcome this problem?

Thanks,

--------------------------------------------------------------------------------

proc glimmix data=logitbank method=quad;

class fid;

model ydat2(event='1') = D1013 fid*D1013

/dist = binary link=logit ddfm=none solution;

random intercept/ subject=fid;

output out =glmout pred =xbeta pred(ilink) =predprob;

covtest;

run;

---------------------------------------------------------------------------------

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Solution

05-20-2017
07:05 AM

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05-15-2017 09:06 AM

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05-14-2017 07:13 AM

Why you include subject term in the independent variables ?

Try option type=chol.

random intercept/ subject=fid type=chol ;

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05-14-2017 07:50 AM

Hi Ksharp!

Thank you for reply!

>Why you include subject term in the independent variables ?

Because I want to include not only random intercept but also random slope.

>Try option type=chol.

I received same warning message: WARNING: Obtaining minimum variance quadratic unbiased estimates as starting values for the covariance parameters failed...

Tissue5454

Solution

05-20-2017
07:05 AM

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05-15-2017 09:06 AM

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05-16-2017 08:37 PM

Hi Ksharp!

Thank you for reply!

I tried PARAM statement and succeed in getting result!

I think the warning message;

"WARNING: Obtaining minimum variance quadratic unbiased estimates as starting values for the covariance parameters failed" tend to come up when the model is too complicated.

In my case, independent variable "D1013" is nonsignificant .

Thank you again,

tissue5454

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05-17-2017 08:12 AM

I am glad that worked and pround of your effort .