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Hello,

I am comparing the fit of two random effects models (one linear, one
gamma with log link) and it seems that the gamma model does not
converge that well (higher autocorrelation, chain is not mixing that
well for one of the coefficients etc.) but the DIC for the gamma model
is lower than the one from the linear model (30414.300 vs. 32470.800).
Also gamma model is known to make more sense for the data I am using
due to skewness, heteroscedasticity etc.

I am a bit unclear of how to interpret these results, and the fact
that gamma model has a lower DIC but it does not converge that well.
Does this mean that I should keep looking for a different model
achieving better convergence and low DIC?

Any suggestion (as well as any useful, enlightening reference) would
be appreciated.

Thanks,

Nicholas


-- 
Nicholas Mitsakakis, MSc, PhD
Research Associate - Biostatistican
Toronto Health Economics and Technology Assessment (THETA) Collaborative
Leslie L. Dan Pharmacy Building, University of Toronto
6th Floor, Room 658
144 College Street
Toronto ON, M5S 3M2
e: [log in to unmask]
t: (416) 946 - 3700
f: (416) 946 - 3719
w: www.theta.utoronto.ca

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