Upper panel: odds ratio of scenario 1 against scenarios 0, 2, and 3. The grey regions indicate the “not worth more than a bare mention”, “positive”, and “strong” evidence as defined by Kass & Raftery (1995). The white region corresponds to “very strong” evidence for one model against the other one. Lower panel: probability of each of the four scenarios considered. We assume here that the other, untested scenarios are not significant (see Sect. 4).