Fig. 2

The number of Boko Haram active cells A₂₀₁₉(ν, μ), varies depending on two model input parameters: their daily speed ν and their maximum distance between two events μ. The smallest number of active cells is obtained when each cell travels ν > 90 kilometres each day and μ > 250 kilometres between consecutive events, which appears unlikely, considering the poor road conditions in the region. A more realistic hypothesis is that cells travel at most ν = 60 kilometres each day and μ = 180 kilometres between every pair of events, which would mean that Boko Haram is fragmented in roughly 53 active cells and 83 total cells