st: Three level mixed random and crossed effects model

[Mrs Mohana Rajmokan <mohana.rajmokan@uqconnect.edu.au>]

Dear List,

I am trying to fit a 3 level random and crossed effects model to a continuous outcome to estimate the respective variance components of each level of the 3  (for doctors)

Level3: Physicians ID
Level2: Patient's ID
Level1: stage ( 1 and 2)

For this study, each doctors have predicted the mortality rate for all the patients in two times. Thus clinician and patient is crossed effect and patient and stage is nested ( I think)

I presumed that  Physicians id is crossed with patient and patient is nested with stage. 

I tried the crossed random effects model for this data

Model1:
xtmixed  mortality_est || doctorsid:R. patient|| doctorsid:R.stage
Model2:
 xtmixed  mortality_est || doctorsid:R. patient|| doctorsid:R. stage||  patient:
Model3:
xtmixed  mortality_est ||stage:||doctorsid:R.patient||z:,variance
but did not converge
Any suggestion will be very appreciated.

Thanks
Kind Regards,
Mohana 


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