Epistemological relevance and statistical knowledge

For many years, at least since McCarthy and Hayes (1969), writers have lamented, and attempted to compensate for, the alleged fact that we often do not have adequate statistical knowledge for governing the uncertainty of belief, for making uncertain inferences, and the like. It is hardly ever spelled out what"adequate statistical knowledge"would be, if we had it, and how adequate statistical knowledge could be used to control and regulate epistemic uncertainty.