Stochastic modeling of a serial killer

M. V. Simkin; V. P. Roychowdhury

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arXiv · 1201.2458

Stochastic modeling of a serial killer

M. V. Simkin·V. P. Roychowdhury

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Abstract

We analyze the time pattern of the activity of a serial killer, who during twelve years had murdered 53 people. The plot of the cumulative number of murders as a function of time is of "Devil's staircase" type. The distribution of the intervals between murders (step length) follows a power law with the exponent of 1.4. We propose a model according to which the serial killer commits murders when neuronal excitation in his brain exceeds certain threshold. We model this neural activity as a branching process, which in turn is approximated by a random walk. As the distribution of the random walk return times is a power law with the exponent 1.5, the distribution of the inter-murder intervals is thus explained. We illustrate analytical results by numerical simulation. Time pattern activity data from two other serial killers further substantiate our analysis.

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M. V. Simkin, V. P. Roychowdhury. 2014-04-28. Stochastic modeling of a serial killer. https://arxiv.org/abs/1201.2458

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