Hi, I’m trying to fit a hierarchical negative binomial (and eventually zero-inflated poisson) model to ~2000 datapoints using a model with ~40 predictors and the QR decomposition. I am able to get the model to fit reasonably well (Rhat, neff, and PPchecks all seem reasonable), but am finding that a…

All parameters ~0 except the final entry in the model matrix (regardless of what that value is)

bgoodri August 8, 2017, 10:46pm 13

Should have N = 1948 columns.

Scaling for poisson model

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