why use prior distributions in hierarchical which model is a gamma distribution based on variance? why use prior distributions what is an example of a prior distribution in a hierarchical model when should prior distributions be used for variance what is used for a hierarchical model to find the variability which model model can be used for variance which prior distribution is best for the variance in a hierarchical model what kind of prior distributions are required for a hierarchical model? prior distribution of the variance why use prior distributions which model uses gamma distributions why do you need prior distribution to a hierarchical model what is the gamma distribution in a Bayesian model what distribution is used in a hierarchical model to measure the variance what distributions are useful to model variability in hierarchical model which prior distribution would fit the variability parameter what is the hierarchical model of variance that has t distribution is variance a prior distribution what is a prior distribution in a hierarchical model