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# s2 poisson watch

1. 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?
2. (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?
3. (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?

higher you mean, no?

4. 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.

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

This is the poisson recurrence formula.

Hope that helps
5. i would like to help, but i dont understand the question
6. So glad all this boring crap is behind me.
7. 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.
8. (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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