 Kullback–Leibler divergences between the whole posterior distributions of the slope and variance do not indicate non-normality.However, the ratio of expectations of these posteriors and the expectation of the ratios give similar results to the Shapiro–Wilk statistic except for very small samples, when non-informative priors are used.Spiegelhalter suggests using a Bayes factor to compare normality with a different class of distributional alternatives.