Mathematics of a Serial Killer

Statistiker haben gestern ein mathematisches Modell für die Morde von Andrei Chikatilo vorgelegt, der in den 80ern über 50 Menschen umbrachte. Dazu haben sie das Verhalten von Neuronen einberechnet sowie verschiedene Faktoren wie Logistik und Planung.

What the authors used as the basis of their analysis was the hypothesis that “similar to epileptic seizures, the psychotic affects, causing a serial killer to commit murder, arise from simultaneous firing of large number of neurons in the brain.” Accordingly, they based their model on neuronal firing – the fact that, once a neuron fires, there’s a refractory period that has to pass before it can fire again. When it does fire, it can trigger other neurons to fire if they’re ready to. As you can imagine, though, those firings aren’t always in sync. So what the authors suggest is that there must be a threshold – that is, when a certain number of neurons fire, the serial killer becomes driven by an overwhelming urge to kill.

In modeling the mathematics of this, the authors note that, “We cannot expect that the killer commits murder right at the moment when neural excitation reaches a certain threshold. He needs time to plan and prepare his crime.” So they built that delay into their model as well. Moreover, the authors also note that the murders do appear in clumps, with the killer more likely to kill after another murder. However, the killings eventually have a sedative effect, pushing the neuronal activity below the “killing threshold” – which is why there are large intervals of time between groups of murders.

When the authors completed their mathematical model, it was remarkably close to the real data.

Scientists Uncover The Mathematics Of Serial Killers (via /.), mehr: hier das PDF „Stochastic modeling of a serial killer“, Technology Review: Mathematicians Reveal Serial Killer's Pattern of Murder, The Criminal Lawyer: Statistics and the Serial Killer