Public commitment:

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CCing cheshirecats as site owner; CCing OB-NYC as witnesses.

> gwern
> I signed up usernames "gwern" and "gwernbranwen" at pivory.com
> I will release login info to you for a ransom.
> The ransom value decreases over time following exponential decay with a half-life of 365/2=182.5 days. It starts at 32 USD on 2012-09-11. I'll allow a 1 day precision.
> Payment is to be sent as Bitcoin using MtGox average price to 1LtiftPcu3AjTbXf2XFCbvNTaeRFL1
yBAy
> After 365 days I will start using the accounts.
> notgwern@tormail.org

Your message in my anonymous site feedback form leaves me deeply
amused, and I applaud your courtesy in setting the 365-day ransom at a
modest $8 (2 half-lives from $32); but I'm afraid I must decline your
offer permanently.

Since there are indefinitely many Internet sites which allow user
signups and publicly visible comments, accepting an extortion on any
of them for any amount exposes me to indefinitely large losses. Hence
by backward induction, there is a clear decision-theoretic verdict
against paying you any sum.

- --
gwern
http://www.gwern.net
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EDIT: Followup predictions:

1. He will reply: http://predictionbook.com/predictions/8217
2. He will not attempt a second time: http://predictionbook.com/predictions/8218