Binomial Negative Distribution

[jorge_manuel_garcia]

[ FlexSim 16.2.1 ]

Hi everyone:

I have a variable that models the number of items sent by a source object. This number follows a negative binomial distribution with a mean value of 339 and variance value of 392.

I'm trying to customize the negbinomial() function but I can't find the correct values for the parameters ("number of successes" and "probability"). I can't find help in the manual and also searched in Wikipedia but I'm lost.

Any help would be appreciated!

Thanks 🙂

PD: To test if the parameters are ok, I use the experimenter, counting the number of items that are sent (once the number is reached, I close the sink's output).

EDIT: I attach a simple model to test it: negbinomial.fsm

[jorge_manuel_garcia · Accepted solution]

I answer myself, I didn't notice that "probability" is a value between 0 and 100 (I was considering it to be from 0 to 1).

number of successes = mean^2 / (variance - mean)

probability = mean / variance