Parsimony of model fits to the autumn 2009 pandemic onset timing: best AICc for each model category.

Each row corresponds to best fit of the most parsimonious model in a given category. The categories are the eight that include EXT (external seeding) plus all possible combinations of AH (absolute humidity), SCH (effect of schools) and SP (spatial transmission). The row in bold indicates the most parsimonious model, as determined by AICc, and ΔAICc gives the difference from the AICc of this model. For each of the categories including SP, the most parsimonious model used the gravity kernel. Table S1 gives an extended version of this table with the different spatial kernels tested separately.