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      1 # Poisson Distribution
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      3 Stats D1
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      5 **Definition:** A poisson distribution is a common distribution that gives the probability of something happening at a point in time (or position or volume) where the probability of it happening at any given time is known. 
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      7 An example of this is the distribution of number of texts receieved in a day where the mean is 12 texts per day. Using this information we can then use a known formula, based on normal distributions, to find the probability that we receive 8 text in a day, less than 8 texts, or any other number of texts. 
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      9 Given this, a poisson distribution does not have an upper bound, but these events become exceedingly rare. As such, the graph has a right skew. 
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     11 The formula is as follows:
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     13 p(x) = (lambda^x * e^-lambda)/(x!)
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     15 In the above we have lambda as the rate of success and x is the number of successes.