plot_normal_normal: Plot a Normal-Normal Bayesian model
Description
Consider a Normal-Normal Bayesian model for mean parameter \(\mu\) with
a N(mean, sd^2) prior on \(\mu\) and a Normal likelihood for the data.
Given information on the prior (mean and sd)
and data (the sample size n, mean y_bar, and standard deviation sigma),
this function produces a plot of any combination of the corresponding prior pdf,
scaled likelihood function, and posterior pdf. All three are included by default.