This function contains the R code for the implementation of Zellner's $G$-prior analysis of
the regression model as described in Chapter 3. The purpose of BayesRef
is dual: first, this R function shows how easily automated
this approach can be. Second, it also illustrates how it is possible to get exactly the same
type of output as the standard R function summary(lm(y~X)). In particular,
it calculates the Bayes factors for variable selection, more precisely single variable exclusion.