Standard deviation

What more info do u need to figure the X% chances u will be down Y dollars on a slot machine given Z spins other than std dev and overall return for that particular machine?

Quote: CardDolphin

What more info do u need to figure the X% chances u will be down Y dollars on a slot machine given Z spins other than std dev and overall return for that particular machine?

How many spins?
one really needs to have the actual result probability distribution for the slot machine to calculate any kind of result return as for a small sample the normal approximation is absolutely meaningless,
as many know it is not even close to being a normal distribution.
How large the sample needs to be to give a close approximation, one cannot know without actual probabilities.

The only slot I can think of where it might be normal after a small sample of spins is the three 7s or nothing slot machine.

added later:
see what others have said
https://wizardofvegas.com/forum/questions-and-answers/math/22690-slot-machine-standard-deviation/

https://wizardofvegas.com/forum/gambling/slots/507-calculating-the-standard-deviation-of-a-slot-machine/