Overfitting: A frequentist illusion?
If you do not have much data, you should use a
simple model, because a complex one will overfit.
This is true. But only if you assume that fitting a
model means choosing a single best setting of
the parameters.
If you use the full posterior over parameter
settings, overfitting disappears!
With little data, you get very vague predictions
because many different parameters settings
have significant posterior probability