Brms setting shape of the negative binomial

Just to confirm,

I see the negative binomial distribution is used in brms (in my case) is

zero_inflated_neg_binomial_log

If I want to input a dispersion from gene expression testing methods (e.g. edgeR)


This histogram shows the dispersion estimation from an external model for 20K genes.

which of these is correct?

  1. shape ~ 1 + offset(log(1/edgeR_overdispersion))
  2. shape ~ 1 + offset(1/edgeR_overdispersion)
  3. shape ~ 1 + 1/edgeR_overdispersion

I am sorry, but I don’t understand your question. Could you perhaps elaborate a bit more?