Spinjack

It's a video blackjack game with a progressive.

Single deck, shuffled every hand, no DAS, double on 9-11 only, no surrender. Naturals pay 2:1 (yes, it really pays 2:1). Suited naturals pay 4:1. Player only wins half his wager on all other wins. So if the player splits or doubles (two hands of $10, $20 total), he can only win $10. I'm thinking the player should never split?

Suited naturals earn the player a bonus round. A wheel is spun around 15 symbols that each have a multiplier for the original bet wagered. There is two of each symbol with the exception of the symbol that represents a bonus spin. Multipliers are: 25, 10, 8, 5, 4, 3, 2. If the player lands on the bonus spin, the multipliers are doubled for the next spin. If the player lands on the bonus spin twice, he wins the progressive amount. Tringlomane, at what dollar amount does the progressive turn positive? ;)

Here is a quick&dirty estimate.

First looking at the (well, infinite deck) tables at https://wizardofodds.com/games/blackjack/appendix/1. Regarding the half stake payout, subtract 0.5 on all stand/hit, and 1.0 on all double/split. You will indeed find that you would never want to double, and splits are at most marginal (i.e. 88vs6).
In a normal game for no double and no split I would estimate the EV to be around -10% (I think the "mimic the dealer strategy" yields -10%, so this number could be a lower limit).

Now there comes the "win only half stake". You would basically play a normal hand with 75% your stake, and paying 25% ante. Hence a $1 bet would return $0.75*0.9 = $0.675 (with normal 3:2 blackjack payout). You get a blackjack with probability 4.83%, where 1/4 of times they will be suited. The non-suited 2:1 part gives you another 4.83% * 3/4 * $0.5 = $0.018 (ignoring Blackjack pushes).

The suited Blackjack gives you 4.38% * 1/4 * $2.5 = $0.027 for the 4:1 payoff. The bonus round gives $7.60 for the first-level multipliers, and $15.20 for the second-level multipliers. These are 4.38% * 1/4 * 14/15 * $7.6 = $0.078 for the first level, and 4.38% * 1/4 * 1/15 * 14/15 * $15.20 = $0.010 for the second level.
The progressive will be X, which gives in EV 4.38% * 1/4 * 1/15^2 * X = 4.86e-5 * X.

In total the return is something like return = 0.675 + 0.018 + 0.027 + 0.078 + 0.010 + 4.86e-5*X = 0.808 + 4.86e-5*X.
Solving for return = 1 yields X = $3950.

Any comments on this kind of estimate ?

There is another Spinjack paytable that does not pay 50% on wins but pays even money on blackjack. It goes to the bonus on a suited blackjack or something like that. It does not have a progressive. I've worked on these machines in the past but it has been a long time since I even heard the game mentioned.

Anyway, this game is on a Pot of Gold, the same types of machines that offer Shamrock 7's and can typically only be found on reservations or in backroom video poker halls. The older machines had a patch to make them play like slot machines/pull tab as it was up to the owner. The new ones may as well but I have never played with them.

IMO, all of these machines are suspect due to this feature. I suppose that is why none of them are in real casino towns and are only found in monopoly reservation casinos, truck stops and back rooms of bars.

Quote: Pokeraddict

IMO, all of these machines are suspect due to this feature.

That's interesting. Can you explain more? The reason I ask is these same machines also have 8/5 JoB with a progressive that turns positive very often. The slot club awards points/bounceback/comps as if it is a slot machine, not VP. Of course, this is all moot if these machines aren't "fair".

Unfortunately games with wheels are allowed to be weighted, so without that specific weighting data, it's impossible to figure out a break-even point.

Quote: RogerKint

That's interesting. Can you explain more? The reason I ask is these same machines also have 8/5 JoB with a progressive that turns positive very often. The slot club awards points/bounceback/comps as if it is a slot machine, not VP. Of course, this is all moot if these machines aren't "fair".

On the older machines there was a rogue patch that could set the machine to play like a slot machine. For example, if the machine dealt you quads and you threw them away it would redeal quads. I do not believe the machine was manufactured with this function, IIRC it was aftermarket software.

The machine I own is a 1996 version and it has this feature. I can turn it off and on. It simply means that if I owned a video poker establishment using these machines and I wanted to lower my variance then I can program the machine to play like a pulltab. It will still pay the proper amount comparable to the pay table, it will just keep me from having too many jackpots in one day. It only pays out when it has a proper hold. I have no idea if the newer versions have this same ability.

This function is presumably why these machines are not allowed in any non reservation gaming jurisdiction. AFAIK, every one of these machines that are live in the US are in tribal casinos, truck stops, cruise ships and questionably legal or illegal back rooms. You will not find them in Nevada, Atlantic City, Mississippi, Iowa, Missouri etc. where commercial casinos are allowed and have laws requiring a game that deals cards to use a proper shuffle.

Even if the Spinjack game is dealing fair cards I doubt the jackpot wheel is weighted correctly. There are a number of Pot of Gold games with these types of jackpot wheel features and the weights are not even on the ones that I am familiar with. There is no way to set them either in the versions I have played with. The wheel weight comes from the manufacturer.

Vision-gaming.com used to show the payback of their games on their website. It looks like they do not anymore. The page used to be here but the Wayback Machine does not have the page saved correctly in either cached version:

vision-gaming.com:80/content/view/78/62/index.html (I didn't hot link because I do not want them to know an AP forum is talking about them).

Maybe you know of some place on the web to find an archived version of that link that will show the payback range.

If you were really interested then you could find these machines on Ebay and contact the sellers and act like you are buying them, then ask them about the Spinjack pay tables. Crazyhugo comes to mind as someone that would know the answer.

Yeah, you are absolutely right!

(missed the part about half wins for other hands)