I have some difficulty to understand the parameters of the negative binomial model in the context of gene expression.
The negative binomial distribution models the number of failures in a sequence of independent and identically distributed Bernoulli trials before a specified (non-random) number of successes r. It has 2 parameters:
r : number of successes until the experiment is stopped
p : success probability in each trial
1) In a context of gene expression and rnaseq: what is success, failure and trial ?
2) The notation of the classical model is NB(r, p). How in DEseq2 it becomes NB(s,d) with s=normalized count and d=dispersion.
Thanks for your help.