Visual data diagnostics revealed that the frequency distribution of geographic distance between case pairs was bi-modal with a cluster of relatively short and another of relatively long distances (Figure 1).
Rainfall pattern is bi-modal with a dry season from June to October.
The fragment length density for cellular DNA is uni-modal, with a narrow range of sizes (first quartile = 153 bp, median = 177 bp, third quartile = 202 bp).
EQ-5D tends to be bi or tri-modal with a gap between full health and the next feasible health state.
Consistent with this observation, we find that the length distribution of divergent regions is bi-modal, with a shorter peak that roughly co-incides with the single peak of uni-directional regions.
The rainfall pattern is bi-modal with a dry season from July to October, a short rain period starting from late November to January and long rains continuing from March to May.
The majority of mapping models in the literature have mapped to EQ-5D, and as a result models are used that are appropriate for the distribution of EQ-5D responses which is typically bi-modal or tri-modal with a large proportion of responses at 1 (see Longworth and Rowen [ 22] for an overview).
The influenza season in Toronto in 2007/8 was bi-modal, with a first "season" beginning on December 16th, 2007 (week 51) and ending February 3th, 2008 (week 6), and a second "season" beginning on February 24th, 2008 (week 9) and ending on May 3rd, 2008 (Fig. 1) [ 13].
Even though propositional provability logic is a modal logic with a kind of "necessity" operator, it withstands Quine's (1976) controversial critique of modal notions as unintelligible, already because of its clear and unambiguous arithmetic interpretation.
