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Statistics conceptual questions

  1. Jan 13, 2008 #1
    Hi all

    I took a course subject in basic statistics but its been so long ago I find that I have mixed up or forgotten some of the concepts so I hope someone here can help me refresh my memory.

    1) Probability starts from 0 to 1, you can have any range of numbers but they cannot exceed 1 or be less than 0 (true/false)

    2) If you have a probability of greater than 0, regardless how small that probability is it will occur given enough time (say infinite amount of time)

    3) I was intrigued by a poster with a list of "facts" that supports creationism, it mention someone about Borel and his law and something about infinite monkeys. I did my google but I am still not a 100% sure of what I am reading so I am simplifying my statements here

    a) Borel law simply states that if you have a small probability, the probability of it occuring is almost negligible
    b) If you have a monkey typing for infinity, then the chance of the monkey typing out Hamlet is almost certain

  2. jcsd
  3. Jan 13, 2008 #2


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    I'm not sure what you mean by "any range of numbers" but, yes, a "probability" cannot be less than 0 nor larger than 1.

    No, that is not true. You can never say something will happen in probability.

    Actually, "Borel's Law" does not say that- that's just directly from the definition of probability. "Borel's Law" (not really a law in the mathematical sense, just a "rule of thumb") says that you can find a "cut off" so that events with probability less than that cut off number can't reallistically happen under whatever conditons you have set (length of time you are letting the "experiment" run, etc.). Of course, that "cut off" will depend upon the additional conditions you have set.

    Theoretically yes. But other than "theoretically" the situaltion is meaningless.

    Probably one of the websites you looked at was this:
    which points out that the "creationist" argument based on "Borel's Law" tend to ignore the non-random determinants in evolution- exactly the things that Darwin's argument was based on. Creationists typically see no intermediate position between "determined by God" and "completely random".
  4. Jan 13, 2008 #3
    I meant any range of numbers between 0 and 1

    so if say the probability of a chimpanzee typing out the whole script of Hamlet is 0.000000000000000000000001 (you get the idea) but if the chimp has infinity time to do it, it WILL NEVER occur?

    What do you mean by non random determinants?

    Thanks for your help, much appreciated!
  5. Jan 14, 2008 #4


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    No, I didn't say anything like that! Are you thinking that the only possibllities are "must happen" and "will never happen"? "Probable" and "possible" are quite different things. Given each letter equally likely, it is possible that, in an infinite string of letters you get "aaaaaa...", all a's. On the other hand, it is also possible that the letter "a" will never occur. Neither one "must" happen.

    I mean, of course, natural selection which will weed out fatal mutations.
  6. Jan 15, 2008 #5
    In statistical terms, how would u define probable and possible?
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