in reply to (OT): Probability problem

.oO( why does this smell like homework? )

Anyway: for each possible 32 bit value there is exactly one other value which XOR's it to zero, so if you assume uniform probability for all values and no correlation between adjacent words the probability is 2**(-32)

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Re^2: (OT): Probability problem
by Anonymous Monk on Mar 09, 2009 at 11:17 UTC

    I work from home, but there is nothing academic about what I do.

    That number is good (perfect for my needs) from a purely theoretic POV, but now consider if you will the reality of a process' memory in a generic application. What influences are likey to increase the likelyhood of the occurance?

[reply]
      Well, it'll be much harder to find a theoretical model than to simply try it. Write a short program (to become on-topic again) to analyze /dev/mem, and tell us what you found.

      (Update: I tried it, and it comes with no surprise that probability is much higher than the theoretical value, because the RAM doesn't contain all that much entropy).

[reply]
[d/l]

      This, again, sounds a lot like homework. Maybe you can tell us the practical application you're using this for?

      Otherwise, it's not really hard to find the underlying assumption of moritz's statement, at least if you haven't slept through your stochastics lectures.

[reply]

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