Create a new mcplot
mcplot.Rdmcplot() initializes a modelcheck object. It follows the ggplot syntax,
which uses a plus sign (+) to define features of model check visualization.
Details
mcplot() uses a list of defaults to generate model check visualizations.
One line of mcplot(model) could generate a complete visualization for
posterior predictive checks. See vignette("modelcheck") for a complete
guidance.