Help me understand this...

[adedpoet]

If a casino claims that it has a 95% return on certain denomination slots...does that mean that, theoretically, if I do 100 one dollar spins on every one of those slots, my money will end up only decreasing a 5% average on each machine? Dumb Question?

[DiamondGeezer]

It is not a dumb question. And the answer is yes.

After 100 spins you would be $95. You lose $5 per $100 played on average.

You can lose a lot of money fast on slots. But see KK's low rolling strategy for a better way!

[vinylweatherman]

It is not a dumb question. And the answer is yes.

Well, it's not quite that simple. There is another factor, the variance, to consider. The higher the variance, the more spins it takes to reach the 95% average.
This often causes problems, with a player complaining they played 200 spins on a high variance slot and got a return under 50%, and that this somehow means the slot has cheated them.

Strictly speaking, in the above case a 95% payout is reached at infinity spins. Some slots can have such high variance that even 10,000 spins can produce a significant departure from a quoted average payout. There is no way to predict whether a specific session of n spins will produce a payout over, or under, the quoted average (assuming the slot is random).

For simple slots, it is possible to calculate this variance, as well as the expected return, and come up with some probabilities that will describe what can be expected on average from a session of n spins - this might take the form of something like "you should be within x% of the average payout in y% of sessions each of n spins"
Slots with pick bonus rounds are harder to calculate values for, since it is not possible to work out the probabilities of the bonus awards, however slots with free spins and multipliers are only a little more complicated, and exact probabilities can be calculated on the assumption the slots are unweighted and random, which applies to most online video slots in "honest" casino software. Video versions of "classic" slots are different, these are usually weighted, and Microgaming's "Fruit Machines" are most certainly NOT random!

[KasinoKing]

If a casino claims that it has a 95% return on certain denomination slots...does that mean that, theoretically, if I do 100 one dollar spins on every one of those slots, my money will end up only decreasing a 5% average on each machine? Dumb Question?

Not a dumb question - but like many people, maybe missing the key factor about slots - variance!
Yes - play that slot with the same value bet for 1,000,000 spins and your return probably would be extremely close to 95%.

But play that slot for 100 spins and the variance could take you to a return of anything from 20% to 2000%+ depending on your luck.
Then bring in the fact that with most online slots you can greatly vary your bets; if you believe in the probability that something with a know frequency of occurring once in N spins is more likely to happen after N spins that it was before N spins, then you can increase your bets in the belief that it will occur...
Doesn't always work of course, but it's seen me make profits from slots play for 4 straight years (using bonuses as well).


(Vinyl replied while I was typing!)