From: Emlyn O'regan (oregan.emlyn@healthsolve.com.au)
Date: Thu Sep 11 2003 - 01:38:54 MDT
I think it's 4/9, but I brute forced it.
Emlyn
> -----Original Message-----
> From: Eliezer S. Yudkowsky [mailto:sentience@pobox.com]
> Sent: Thursday, 11 September 2003 3:46 PM
> To: extropians@extropy.org
> Subject: Re: Today's evil Bayesian math problem
>
>
> Eliezer S. Yudkowsky wrote:
> > Suppose that a bowl has 5 red chips and 3 white chips. We
> sample chips
> > from the bowl using the following procedure: On each round
> we draw a
> > random chip, replace it, and then add another chip of the
> same color to
> > the bowl. For example, if on the first round we happen to
> draw a red
> > chip, there would then be 6 red chips and 3 white chips to
> draw from on
> > the second round.
> >
> > Given that a white chip was drawn on the fourth round, what is the
> > probability that a white chip was drawn on the second round?
> >
> > (This problem is extra bonus evil because it's so easy if
> you know the
> > rules.)
>
> Evil Hint #1: Not only is it possible for you to do this
> problem in your
> head, the answer can be obtained in ONE step.
>
> --
> Eliezer S. Yudkowsky http://singinst.org/
> Research Fellow, Singularity Institute for Artificial Intelligence
>
This archive was generated by hypermail 2.1.5 : Thu Sep 11 2003 - 01:50:04 MDT