### Jennings Governor 'win percent' rate question...

Hi

I'm a friend of a collector (my next door neighbour here in Edinburgh Scotland) and he asked me, just out of interest, for fun, to calculate / confirm some winning percentages on his classic, and mint condition Jennings Governor Slot Machine...

I've been trying to calculate these winning probabilities he was wondering about (pics attached) and I am a bit stumped on my findings so hoped someone could help!...

Here's some background info:

- The guy he bought it from said previously the owner added two LEMONS to Reel 1 to decrease a player's win rate.

- But currently my neighbour's fully working, '1 shilling = 2 plays version' has been restored to its original state ie those cheeky lemons are now removed.

- I attempted to calculate both previous/current winning %'s... but the outcome seems really low (30.9% / 44.6%) compared to what the machine graphic actually states, leads us to believe?!: 'A MINIMUM OF 75%'...?!??!

- For the current version, (see image attached), I initially calculated 22.4 and then realised, when I played it, you get 2 shots per coin, so simply doubled my final winning % calculation.

So, yes, I'm a bit stumped... myself and my neighbours did some manual tests and averaged about 50% winning rate so that doesn't really help matters but kind of confirms the 44.6% winning rate I calculated but it doesn't explain why the machine itself says '75%' and I've even read on this forum that it's a very high paying machine and someone stated 80% as a pay out rate for it... very low-volatility!! (I think I used that term correctly!)

Any help would be much appreciated.

Thanks!

I'm a friend of a collector (my next door neighbour here in Edinburgh Scotland) and he asked me, just out of interest, for fun, to calculate / confirm some winning percentages on his classic, and mint condition Jennings Governor Slot Machine...

I've been trying to calculate these winning probabilities he was wondering about (pics attached) and I am a bit stumped on my findings so hoped someone could help!...

Here's some background info:

- The guy he bought it from said previously the owner added two LEMONS to Reel 1 to decrease a player's win rate.

- But currently my neighbour's fully working, '1 shilling = 2 plays version' has been restored to its original state ie those cheeky lemons are now removed.

- I attempted to calculate both previous/current winning %'s... but the outcome seems really low (30.9% / 44.6%) compared to what the machine graphic actually states, leads us to believe?!: 'A MINIMUM OF 75%'...?!??!

- For the current version, (see image attached), I initially calculated 22.4 and then realised, when I played it, you get 2 shots per coin, so simply doubled my final winning % calculation.

So, yes, I'm a bit stumped... myself and my neighbours did some manual tests and averaged about 50% winning rate so that doesn't really help matters but kind of confirms the 44.6% winning rate I calculated but it doesn't explain why the machine itself says '75%' and I've even read on this forum that it's a very high paying machine and someone stated 80% as a pay out rate for it... very low-volatility!! (I think I used that term correctly!)

Any help would be much appreciated.

Thanks!

### Re: Jennings Governor 'win percent' rate question...

I don't know if this will help or hinder, but here goes.

Firstly even the restored reel order is not a factory produced one so this might change the odds from what it says on the machine. It's very close but the only original set it could be is V12-92, which is exactly the same except the second symbol on reel one is a BAR, not a cherry, giving you two BAR on reel one. (This is normal on almost all Jennings).

Below is the payout calc chart for V12-92. As you can see, with the BAR in place the payout % is a staggering 87.05% (but this a calculated possibility. The actual could be at least 10% less). These charts were worked out by Daniel Mead and are accurate within their scope.

I can only guess that removing the BAR drops the % to the 45% you come up with.

Firstly even the restored reel order is not a factory produced one so this might change the odds from what it says on the machine. It's very close but the only original set it could be is V12-92, which is exactly the same except the second symbol on reel one is a BAR, not a cherry, giving you two BAR on reel one. (This is normal on almost all Jennings).

Below is the payout calc chart for V12-92. As you can see, with the BAR in place the payout % is a staggering 87.05% (but this a calculated possibility. The actual could be at least 10% less). These charts were worked out by Daniel Mead and are accurate within their scope.

I can only guess that removing the BAR drops the % to the 45% you come up with.

### Re: Jennings Governor 'win percent' rate question...

Oh, that's very interesting!!!

And without me delving back into my browser searches of the last few days I do recall someone mentioning that the 1st reel originally had 2 TIC's or BARS! Which would tie in with what you are saying!

I actually mentioned that exact fact to my neighbour yesterday but didn't take too much note of it as the TIC-TAC-TOE winning combos are so rare and in my mind wouldn't have made up my calculated % from 44>75 solely by themselves but the more I begin to understand the probability, the more I think that simply having that EXTRA BAR/TIC on row one [in place of the cherry] would bring the winning % up to exactly what Jennings originally state and promise!

I'll add this into my equation/file and keep you posted

Thanks!

ps if only ALL gambling had an 85+ win rate these days!?! That's crazy high!

And without me delving back into my browser searches of the last few days I do recall someone mentioning that the 1st reel originally had 2 TIC's or BARS! Which would tie in with what you are saying!

I actually mentioned that exact fact to my neighbour yesterday but didn't take too much note of it as the TIC-TAC-TOE winning combos are so rare and in my mind wouldn't have made up my calculated % from 44>75 solely by themselves but the more I begin to understand the probability, the more I think that simply having that EXTRA BAR/TIC on row one [in place of the cherry] would bring the winning % up to exactly what Jennings originally state and promise!

I'll add this into my equation/file and keep you posted

Thanks!

ps if only ALL gambling had an 85+ win rate these days!?! That's crazy high!

### Re: Jennings Governor 'win percent' rate question...

Yes, you are right, the closer you look the more it makes sense. The key is that the extra BAR comes into play more often than you might think because it's part of the anywhere in the window payouts.

- badpenny
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### Re: Jennings Governor 'win percent' rate question...

I just like the shiny chrome, the sound and … well, looking at them I suppose.

BP

BP

### Re: Jennings Governor 'win percent' rate question...

Hi spumker, welcome.

I am not a bandit man and know little about them but I do like to work out payout percentages. Bear in mind that the 'chances of winning' differ to that of 'return to player percentage' and it is this that the 75% refers to. I have only looked at your table number one (without the added lemons) and have noticed at least one discrepancy with the chances of winning table. For instance, the cherry/any/any shows 800 chances of winning but I make it 520 as the cherry/cherry/any and cherry/bar/any have already been accounted for in your award card. One or two other lower combinations may not be the same as my calculations. This will no doubt reduce the chances of winning percentage. Have a look at these and see if you agree. Also, whatever is in the jackpot has to be added to the 'coins returned' - I haven't paid much attention to that column yet, but it will have an impact on the return to player figure.

I am not a bandit man and know little about them but I do like to work out payout percentages. Bear in mind that the 'chances of winning' differ to that of 'return to player percentage' and it is this that the 75% refers to. I have only looked at your table number one (without the added lemons) and have noticed at least one discrepancy with the chances of winning table. For instance, the cherry/any/any shows 800 chances of winning but I make it 520 as the cherry/cherry/any and cherry/bar/any have already been accounted for in your award card. One or two other lower combinations may not be the same as my calculations. This will no doubt reduce the chances of winning percentage. Have a look at these and see if you agree. Also, whatever is in the jackpot has to be added to the 'coins returned' - I haven't paid much attention to that column yet, but it will have an impact on the return to player figure.

### Re: Jennings Governor 'win percent' rate question...

I always thought, and this being a US Jennings, that the actual US law was a minimum 75% payout? I remember seeing percentages stated on many bandits including some of my segas and the later electro mechanical machines too. But yes, of course, dodgy operators and their tampering are pretty common hence extra fruits and blanked off payout cutouts etc. I think in the UK there is no minimum payout by law but don't operators have to state on the machines the actual average percentage? I did this sort of calculation for my Vale Roma Baromat conversion and it was a measly 62% payout and actually i think that is fairly accurate because its very difficult to win any upper wins, like 8 or 10. On modern day machines some say the statement "This machine is random" or "This machine is compensated", the latter meaning that it can never lose for the operator. Early examples of this were the Peter Simpner Club Machines, and all percentages stated in the present time are over the lifetime of the machine.

### Re: Jennings Governor 'win percent' rate question...

I don't think there ever was a fixed percentage payout in the pre electric days I don't see how that is possible, on a machine with random stops and a fixed order of symbols. You can have a probability of winning but not a fixed percentage, not for certain. You could pull the handle 200 times and not get three BELLS then get them twice in a row. We have ALL done both of those LOL. As Malc says, over the machines lifetime, perhaps, but how could you tell as the lifetime would vary?

All modern Electric machines can be keyed to a percentage payout which the operator can vary. On cruise ships it's easy to see the machines pay out much more often on the first two days of a cruise and the last day and the profit comes on sea days. In the USA today the fixed payout laws vary between states. In Nevada it's 75% in New Jersey it's 83%. The native Indian run casino are under no obligation to disclose their payout percentage BUT the compact (a loose contract) native Indian run casinos enter into with the US version of the gaming commission to get their licence says they must pay 96% to 98% on slot machines.

These amounts do in fact not apply anyway, either in the US or the UK, as by adding only one "feature" such as "double or nothing" the percentage can be drastically reduced. As many modern machines offer the winner several extra chances to win more (or lose the lot) the only way you could hope to be within the fixed percentage is to always collect the first straight win amount.

All modern Electric machines can be keyed to a percentage payout which the operator can vary. On cruise ships it's easy to see the machines pay out much more often on the first two days of a cruise and the last day and the profit comes on sea days. In the USA today the fixed payout laws vary between states. In Nevada it's 75% in New Jersey it's 83%. The native Indian run casino are under no obligation to disclose their payout percentage BUT the compact (a loose contract) native Indian run casinos enter into with the US version of the gaming commission to get their licence says they must pay 96% to 98% on slot machines.

These amounts do in fact not apply anyway, either in the US or the UK, as by adding only one "feature" such as "double or nothing" the percentage can be drastically reduced. As many modern machines offer the winner several extra chances to win more (or lose the lot) the only way you could hope to be within the fixed percentage is to always collect the first straight win amount.

### Re: Jennings Governor 'win percent' rate question...

That's very interesting coppinpr, thanks for sharing. I do have a modern Japanese table top pachislo slot machines (in Japan, they have to be destroyed or exported after two years). It's an incredible thing, and the odds on this one are a minimum of 96% and highest at 106%. You put it into a mode and select from 1 to 6 (these being the odds and the way the game plays out, with different features accordingly). Because they are token play and tokens are exchanged for goods, they can afford to make them loose on 106% because they simply make the token exchange for goods higher. Of course a loose paying machine attracts people to play the not so generous machines alongside it, so tactics of the Japanese pachi parlours/casinos is they change the odds regularly on different machines. It can be operated with US quarters or UK 10p coin but would prove highly unprofitable if doing so.

### Re: Jennings Governor 'win percent' rate question...

As you say Malc, these days in the UK operators have to display the average percentage return to player/payout - you may need sharp eyes to see it. There is no legal minimum but the industry suggests it should be a minimum of 70%. Mills bandits were factory set at 74%. This is over XYZ plays which could be a huge number and is assumed randomness. It's all about odds, for instance the chances of getting a jackpot of three bells if there was only one bell on each reel and it is a three reeler with twenty symbols on each reel would be 1 in 8000 or odds of 7999/1 but you are not going to get anywhere near 8000 coins returned so there is an inbuilt profit for the operator. A simple way of looking at it would be the toss of a coin. Both heads and tails have an even chance of happening but you could get 6 heads on the trot so tails has some catching up to do but at some time they will even themselves out sooner or later, that's the maths of it. There is 1 in 64 probabilities of getting 6 heads on the trot at a time in the sequence that you determine, odds of 63/1.

Last edited by 13rebel on Sun Oct 06, 2019 12:35 am, edited 2 times in total.

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