How to Catch a Serial Killer with Hannah Fry

Hannah Fry (University College London) explains how police detectives use maths to help them to catch a serial killer.

Interview with Dr Tom Crawford from the University of Oxford, recorded at the Isaac Newton Institute.

Produced by Dr Tom Crawford, with thanks to Hannah Fry and the Isaac Newton Institute.

Follow Tom Crawford on Facebook, Twitter and Instagram @tomrocksmaths.

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[warrenburroughs]

The probability of me watching a video featuring Hannah Fry? Statistically significant.

[zizhiqu]

Hannah Fry delivers this with all the calm, sass and nonchalance of a serial killer who knows she has gamed the system.

[aadityasingh]

"Ferb, I know what to do in the weekend"

[lordsalisbury]

I like the bit where she says "I know what you're thinking, if you're a serial killer and you know as if a lot of serial killers are doing advanced mathematical modelling and are watching this video as job research. I'm sure most people watching this were actually just thinking how much they love Hannah Fry.

[TheOriginalItchyman]

I could listen to Hanna talk about anything for all my life and I'd be happy.

[CycolacFan]

Very useful, thanks Dr Hannah. Any top tips on disposing of a body? Should I dig the hole first, or make him dig the hole?

[brianmulholland]

If I were a serial killer, the first thing I would do is not kill anyone within my state, never repeat the same method, and never select victims with anything in common, and never dispose of the body the same way. The best way to not get caught as a serial killer is to not let the police even REALIZE two of your murders are connected. For non-serial killers, the route to solve is to always look for connections. Serial killers choose semi-random victims that they don't know, so it's always the repetition that gets them caught.

But then, a serial killer is acting on compulsions...and those compulsions want to repeat things. So if I were a serial killer, I suppose I would not choose my own plan.

[stSilence]

brilliantly explained. Need more Hannah Fry! :)

[gowzahr]

The title makes it sound like we're going to use her as bait to catch the killer.

[welshpete]

Interesting as always, thank you for going to all the trouble and posting !

[mlguy]

I may use this for my interactive presentation on ML for secondary schools. Thanks!

[davidioanhedges]

1. pick a truly random location
2. only kill based on this random location being your home
3. Don't get caught

[Black.Red]

*”Let’s say you’re a serial killer…”*

How did she know?

[pointzerotwo]

Though I already knew it as fiction, Miles sent me here to comment that only actors do mathematics on fiction.

[Roger]

I showed this graph to the police, they still haven't figured out that my family was murdered by me, they said "there's no way he did it, his too close on the x-axis it's not possible".

[Mooocheropordis]

Thanks for pointing out murder is illegal, wasn't too clear on that 😮

[greamespens]

Hear you neighbours having an argument and when one of them is out bump off the other and when their partner comes back they get nicked and you can watch bargain hunt in peace in future

[DAVEHARSTON]

I watched this video 1 year ago today and I have around 17 scalps so far so I can definatly say its 100% correct

[tawnlr]

Don't waste your time on serial killers, read Miles W. Mathis instead.

[Mr_Fu_Manchu]

I would start analysing what victim did in the last week and to whom has interacting but, that would work too.