Inverse poisson

[Dieter]

(10-05-2015 01:05 AM)lrdheat Wrote:  Sorry about not including probability...Using average of 1E9, at p=.99, what is correct value for inverse poisson? I'm guessing the Prime is closer than the Casio 9860gii.

This depends on whether you look at the left hand or right hand sum, i.e. the probability P(x≤X) or P(x>X). ;-) The results I posted refer to the former.

For p=0.99 there is a problem with the 34s regularized Gamma function (which returns values > 1 – sounds like a bug). Despite this my program returns an integer result of 1000073565 < x < 1000073566. With a corrected Gamma function the program returns...

x = 1000073565.814426761131158060038507

...which, according to Wolfram Alpha, seems to be the correct 34-digit value for the 99%-quantile.

So the Prime is correct.

Dieter

Edit: sorry, the originally posted result was off by one... #-)