- Joined
- May 22, 2012
Right, lately we have had many people, mainly newbies asking about RTP and thinking they are being ripped by lower than advertised temporary RTP's.
So, in my own little way I hope this explanation helps get your heads around the issue.
So, in my example I am using a TRTP (theoretical return to player) of 95% but for simplicity's sake it will be achieved via the random number generator (RNG) over a mere 100 spins..........
So, the ultimate LOW VARIANCE example would be: You have 100 spins and win 0.95 EVERY spin. (you've all see Starburst lol...)
For my simplified example we have the ultimate HIGH VARIANCE slot - out of 100 spins, 99 will pay bugger-all and one will pay 95.0.
So, I make a deposit, and on my fiftieth spin I win the 95 pounds. I cashout. My RTP for the session (50 played, 95 won) is 190% Yippee.
So, player B coming along makes a deposit of 100. (bear in mind the slot must pay the 95 in every 100 spins.) He obviously loses for the next 50 spins as you just had the 95 win. So, 50 down he now unknowingly enters the next cycle of 100 spins. This time, although he doesn't know it, the next 95 win is going to come on the very last of the 100 spins. He has now lost therefore his whole hundred with a 0 RTP. He deposits another 50 and on the last spin gets the 95 win. His RTP for the last 50 deposit is 190% same as the first player's 50 deposit session. Only he's lost 100 beforehand so his OVERALL RTP at the site is 100%/150 units x 95 unit win = 63.33%.
He will then come on here pissing and moaning (as many of us have) 'it's rigged/awful site/terrible slot'.
BUT....look at the stats - the slot has taken 200 units, paid 2x95 units out therefore has hit it's TRTP of 95%.
OK, so now we see that, complicate the example; turn the 100 spins into 10 million, fill the pool the RNG selects from with any permutation that adds up to 95% of 10 million units i.e. 1 million 0.5x stake values, 500,000 10x stake values, 50 1000x stake values etc. Obviously free spins scatter triggers and values will come into it and of course the likelihood of any win in the pool will be reflected in the reel maps by frequency of symbols - whether the reels are stopped individually with 5 random stops (some are allegedly) or a simple pseudo-reel graphic is computed or selected to match your individual RNG selection (as in MG slots almost certainly and definitely in WMS).
Lastly, the pool is a 'rolling pool' - it doesn't have a fixed end of 10 million as in my 100-spin example (which is more like an AWP works admittedly) but the RNG value you've just had goes back in the pool so there are always the same chances of the player picking any named RNG value on every spin.
(This explains why some casinos like Enzo at 3Dice will openly tell you that although all their slots for example's sake are 95% TRTP, some to date have paid to all players ever 97.8% and some only 93.2% - this is simply the long term effect of luck going either for or against the casino on any particular game, although the median RTP to date on ALL their games together would very likely be nearer the 95%)
Now imagine your 900 deposit will get you 900 goes. You dip your 'hand' blind into the pool in one go and grab 900 values which total 2700 - great, you've grabbed 1 1000x stake win, 500 2x stake wins 397 no-wins and 2 350x stake wins. You're 1800 up, and have had a session RTP of 300%
Next time you only grab 900 values which total 450 - you've had a bad session with a 50% RTP but overall you casino RTP to date is 1800 deposited and played, 3150 taken out = 175%.
Hope this example helps players understand both basic variance and more importantly what session RTP, theoretical RTP and overall personal account RTP actually mean. It is easy to focus on a few bad sessions and not calculate how previous wins and cashouts may mean your overall RTP at that particular site can still remain quite favourable.
So, in my own little way I hope this explanation helps get your heads around the issue.
So, in my example I am using a TRTP (theoretical return to player) of 95% but for simplicity's sake it will be achieved via the random number generator (RNG) over a mere 100 spins..........
So, the ultimate LOW VARIANCE example would be: You have 100 spins and win 0.95 EVERY spin. (you've all see Starburst lol...)
For my simplified example we have the ultimate HIGH VARIANCE slot - out of 100 spins, 99 will pay bugger-all and one will pay 95.0.
So, I make a deposit, and on my fiftieth spin I win the 95 pounds. I cashout. My RTP for the session (50 played, 95 won) is 190% Yippee.
So, player B coming along makes a deposit of 100. (bear in mind the slot must pay the 95 in every 100 spins.) He obviously loses for the next 50 spins as you just had the 95 win. So, 50 down he now unknowingly enters the next cycle of 100 spins. This time, although he doesn't know it, the next 95 win is going to come on the very last of the 100 spins. He has now lost therefore his whole hundred with a 0 RTP. He deposits another 50 and on the last spin gets the 95 win. His RTP for the last 50 deposit is 190% same as the first player's 50 deposit session. Only he's lost 100 beforehand so his OVERALL RTP at the site is 100%/150 units x 95 unit win = 63.33%.
He will then come on here pissing and moaning (as many of us have) 'it's rigged/awful site/terrible slot'.
BUT....look at the stats - the slot has taken 200 units, paid 2x95 units out therefore has hit it's TRTP of 95%.
OK, so now we see that, complicate the example; turn the 100 spins into 10 million, fill the pool the RNG selects from with any permutation that adds up to 95% of 10 million units i.e. 1 million 0.5x stake values, 500,000 10x stake values, 50 1000x stake values etc. Obviously free spins scatter triggers and values will come into it and of course the likelihood of any win in the pool will be reflected in the reel maps by frequency of symbols - whether the reels are stopped individually with 5 random stops (some are allegedly) or a simple pseudo-reel graphic is computed or selected to match your individual RNG selection (as in MG slots almost certainly and definitely in WMS).
Lastly, the pool is a 'rolling pool' - it doesn't have a fixed end of 10 million as in my 100-spin example (which is more like an AWP works admittedly) but the RNG value you've just had goes back in the pool so there are always the same chances of the player picking any named RNG value on every spin.
(This explains why some casinos like Enzo at 3Dice will openly tell you that although all their slots for example's sake are 95% TRTP, some to date have paid to all players ever 97.8% and some only 93.2% - this is simply the long term effect of luck going either for or against the casino on any particular game, although the median RTP to date on ALL their games together would very likely be nearer the 95%)
Now imagine your 900 deposit will get you 900 goes. You dip your 'hand' blind into the pool in one go and grab 900 values which total 2700 - great, you've grabbed 1 1000x stake win, 500 2x stake wins 397 no-wins and 2 350x stake wins. You're 1800 up, and have had a session RTP of 300%
Next time you only grab 900 values which total 450 - you've had a bad session with a 50% RTP but overall you casino RTP to date is 1800 deposited and played, 3150 taken out = 175%.
Hope this example helps players understand both basic variance and more importantly what session RTP, theoretical RTP and overall personal account RTP actually mean. It is easy to focus on a few bad sessions and not calculate how previous wins and cashouts may mean your overall RTP at that particular site can still remain quite favourable.
