The estimated basic reproduction number, R0, for a Markov SEIR model in a multi-type population as described in [32], based on the real infection process (who infected whom) plotted against the computed R0, assuming homogeneous mixing, based on the estimated epidemic growth rate, α, and given expected infectious period (5 days) and expected latent period (10 days). The infectivity is chosen at random, such that the theoretical R0 is uniform between 1.5 and 3. The estimate of α is based on the times when individuals become infectious. In (b), a box plot of the ratios of the two R0 estimates (the estimate based on the homogeneous mixing assumption divided by the estimate based on the real infection process for each of the 250 simulation runs) is given. (Online version in colour.)