Exercise 3.9 Show that the HPD interval for an odds ratio is not invariant to a switch of the groups by interchanging in Table 1.1 the two columns. More specifically if [a, b] is the HPD interval for the odds ratio in the original setting, then [1/b, 1/a] is not the HPD interval anymore for the odds ratio with the columns switched. However, this property holds for a classical CI. Note also that there is no such difficulty for γ = log(or).