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  1. OK, with apologies to all, I am going to weigh in on the concurrent birthday probability question.

    First, Benson is correct that finding a poisson distribution is an alternate method for finding the solution. But that doesn’t help much. Lets see what we can understand without ANY math.

    First Step: Understand the precise question posed. Always a good idea, but so often overlooked. What is the probability that in a group of people a pair of people will have the same birthday?
    So the answer is going to be in terms of a pair. You will have to know how many pairings are possible, being careful not to double count. (ie Lech/Benson is the same pair as Benson/Lech). Also this tells us the first data point will be for a group of two people. Intuitively, we know that the chance of any two people having the same birthday is low.

    Step Two: What are the facts/ What are the assumptions.

    1. There are 365 days in a year. Actually wrong because of Leap Years.

    2. The exact same number of people are born on each day of the year. I have no idea if this is true. However if it is true, out of a group of 367 people there is 100% probability that 2 will have the same birthday. If not true then the problem is way more difficult.

    3. There are no twins allowed

    Step Three: What would the answer reasonably look like:

    At the first data point, a single pair, the probability is low.

    Lets make 50% probability the next data point. We gewt there pretty quickly so we can draw a near vertical line on the graph

    At 90% probability, the line curves around to nearly horizontal. We know that this number is pretty far above the 50% mark, but also less than the maximum. So are graph is now curving dramatically toward a horizontal line.

    At 100% probability, the line is completely horizontal.

    CONCLUSION: We pretty much can figure out in a general sense everything about this without doing a single, tedious factorial.

    Voila!

    (Apologies to all who are bored to tears by now. Hope that is not the entire Plusa population.)

  2. I am a Unitarian Unilateralist. Not to get into too much theology, the religion does not have a creed or dogma, but instead has common principals. Its roots are Protestant, but the religion really stopped being Christian a century ago.

    There is a wide range of believe systems in the church, with atheist/agnostic/humanist probably being the biggest.

    Kind of hard to explain, even though I have been a practicing member for 7 years.

    The services are church-y, but the sermons are all over the place.

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