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    when using poisson distribution and it gives a question like whats the probability (3<=x<=8) why does this mean the probability that x is between lower than or equal to 8 and lower than and equal to TWO. Also is there a list where it shows me where questions like p(6<=x<9) translate to?
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    (Original post by MIKE ESSIEN IS QUITE SICK)
    when using poisson distribution and it gives a question like whats the probability (3<=x<=8) why does this mean the probability that x is between lower than or equal to 8 and lower than and equal to TWO. Also is there a list where it shows me where questions like p(6<=x<9) translate to?
    Fish distribution?
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    (Original post by MIKE ESSIEN IS QUITE SICK)
    when using poisson distribution and it gives a question like whats the probability (3<=x<=8) why does this mean the probability that x is between lower than or equal to 8 and lower than and equal to TWO. Also is there a list where it shows me where questions like p(6<=x<9) translate to?
    X~(3\leq x \leq 8)

    higher you mean, no?

    P(X\geq 3) = 1 - P(X\leq 2)

    am I sort of answering your question or not really?
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    The poisson distribution models the likelihood of the number of events in a random process. So when you have the probability of (3<=x<=8), this is the probability that there will be between 3 and 8 random events in the specified unit of time.

    The way of calculating P(3<=x<=8) involves using P(x<=8) - P(x<=2) (i think that's what you were referring to) because its the probability that there are less than 8 random events minus the probability that there are less than 2 random events.

    There are no tables, this is strictly calculated using the formula. I just use my ti-84 calculator though, because it has the capacity to calculate most distributions.

    There is one trick that might help you:

    P(X = x+1) = (mean/(x+1))(P(X=x))

    This is the poisson recurrence formula.

    Hope that helps
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    i would like to help, but i dont understand the question
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    So glad all this boring crap is behind me.
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    You just need to know that poisson is french for fish. That will come in more useful than the poisson distribution ever will for you.
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    (Original post by MIKE ESSIEN IS QUITE SICK)
    when using poisson distribution and it gives a question like whats the probability (3<=x<=8) why does this mean the probability that x is between lower than or equal to 8 and lower than and equal to TWO. Also is there a list where it shows me where questions like p(6<=x<9) translate to?
    P(3<=X<=8)=P(X<=8)-P(X<=2)


    The best way to think of it is to consider a graphical representation of the poisson; http://www.me.utexas.edu/~jensen/ORM...mg/poisson.jpg here's an example (the numbers are different to yours but you should still get the jist)

    Basically, P(3<=X<=8) means what is the probability that X is between 3 and 8 inclusive right? So, you want to know the probability X is less than or equal to 8 minus the probability X is less than 3 (i.e. less than or equal to 2)

    Also, I don't quite understand your 2nd question
 
 
 
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