Analysis of casino shelf shuffling machines (2011) | Hacker News Reader

Analysis of casino shelf shuffling machines (2011)

arxiv.org

46 pointsColinWright27 comments

I bet most people are unaware how expensive card shufflers are $20,000 US is typical. But really leasing shufflers is far more common.

One company, Shufflemaster (SHFL), had a monopoly on the market. But Bally bought SHFL and then Scientific Games bought Bally.

I've heard the patent (or whatever it is) SHFL has expires very soon. There may be a rush of new companies trying to get in on this expensive market.

Other ridiculously expensive casino equipment is a small mirror/prism. It's affixed to a card table in front of the dealer. Two cards are inserted face down but the prism reflect back the card number and suit so the dealer can see it. This small simple thing is only leased costing $100 per table per month.

I'm a recently suddenly out of work slot tech forgive my reminiscing.

Edit: table not tanke

I built myself a somewhat fancy card table a couple of years back, and wanted to add an authentic built-in casino-style shuffler for it, and was blown away by how much these things go for. Additionally, it is very difficult to buy them second-hand: I would guess Shufflemaster may have some agreement with their customers that limits their availability in the after-market. The few you can actually find on eBay still go for multiple thousands of dollars! I chose to go without and just shuffle the old fashioned way.

The market for a reasonably priced (under $500) in-table shuffler is probably very niche, but it exists and is an opportunity. As far as I'm aware there is only one other company with a decent one, and I won't link to them because of their extremely poor (borderline scammy) service. If you're a poker table builder though you've heard of the company and probably read the horror stories in the forums. Ripe for 'disruption'.

You find it interesting that Shufflemaster iDeal shufflers have a camera in them that reads each card that goes by it and stores that card in memory. You tune a specific manufacturer style of cards since they all are slightly different.

So if a player later disputes and says he swears he had an Ace of spades the pit boss looks back in the shuffler history to see that hand given to that player did not have an Ace of spades it was a 4 of spades.

Shufflemaster iDeal shufflers have a camera in them that reads each card that goes by it and stores that card in memory

One would hope that the machine actually uses that information in real time. Specifically to check for missing or duplicated cards.

But the casinos probably wouldn't care for that feature. Their edge improves markedly if an Ace goes "missing".

Players find it hard to notice missing cards, because casinos generally use perhaps 6 decks at a time, and many cards are not exposed to the players during the course of dealing them from a shoe (often a casino won't deal perhaps 25% of the cards). But 23 vs 24 Aces does make a difference in the casino's edge.

It may not seem like much, but with perfect play the house edge is only about 0.4% in Blackjack[1] (depending on exact rules), so every little bit helps.

[1] https://wizardofodds.com/games/blackjack/calculator/

> One would hope that the machine actually uses that information in real time. Specifically to check for missing or duplicated cards.

They do it's a very heavily used feature of the iDeal shuffler the One2Six model shuffler doesn't have a camera. That was a big problem you often get missing cards that aren't really missing. Sometimes (many times) moisture would cause the card to curl pulling the card corner with its number and suit away from the area the camera views.

The main problem was a deck that wasn't in the database but I had to find one close enough to tune in. It was OK but many prompts of missing cards when there were there.

Other problems are table felt fibers sucked in, makeup, hair around rollers, card dust all get on the lens and around the rollers.

Thanks for the extra details.

One of the things I just love about HN is all of the "inside baseball" stuff we get to hear about.

slot tech

Do you mean the 'digital' ones i.e. the games with 3 or 4 3x3 rasters where one has to place 3x1 lines and try to match the fruits and bells and whatnot? If so could you share some knowledge on how the randomization on these things work? When I play these I can't help but wonder how this works. I'm fairly sure it's not 100% work of a random generator but rather finely tuned to give enough so the player comes back, but not too much. And at the same times there's a weight assigned to certain piecs and combinations thereof. And possibly there's even some rules like 'max number of points per x games can be no more then y' etc. All in all, it feels pretty complicated but I might be completely wrong.

The magic is US Patent 4,484,419. Known in the industry as the "Telnaes" patent after it's inventor.

https://patents.google.com/patent/US4448419A

This invention is where slots migrated from physical reels to virtual ones. A reel could now have thousands of "stops" compared to 10 or 20 on the older machines. The physical reels were now driven by stepper motors to show the landing position of that virtual reel. Having virtual reels with many more stops also meant the jackpots could be a lot higher than the typical 1-in-20^3 possibility of a physical reel group.

After some time, it was realized that the careful design of these virtual reels is where the slot designer can create many many "oh-so-close" combinations of the physical symbols without making the player land any closer to the jackpot than normal. And that semi-positive reinforcement draws the player in to play more.

One of the most recent Planet Money episodes, #773: Slot Flaws Scofflaws, explores slot machine design, to some extent. It's a fun listen.

http://www.npr.org/podcasts/510289/planet-money

Only digital yes although some have physical reels but the actual reels are just for show they have no actual effect even if you move them (it will show reel tilt).

The lower the award the more symbols are on a reel, there are also virtual stops since a reel would need to have a diameter of 2 metres to fit them all on. Blank spaces are also stops. There is only one top award symbol on each reel.

Some slots alter the odds the higher you bet but those are not really common or at least we never had such slots.

I wasn't involved in that much detail to know how each slot machine OS worked other than get the machine working so it can be played. But generally speaking there are multiple PRNGs on old terminals new HD/CF based slots would have similar in software. Nothing is truly random of course, hence the pseudo part, due to limitations of the hardware and the crystal oscillators chips or software used to generate random numbers.

It's random enough although it very common to see a hold of over 100% and way under the optioned in percentage. Usually the higher the denom the higher the payback to the player e.g. 1 cent maybe 80% and $1 95% and $5 may be 98% but those are over one or ten million spins not per player.

Then add in progressives which add to the percentage so a 1 cent progressive at 80% + maybe 5% for the progressive math makes 85% payback. Recently random progressives that award for no reason i.e. you don't need the top five symbols at max bet to win. Some progressive award within a range starts/resets at say $500 won't go over $1000 so if it's $999 it will go soon (people fight over them at that point).

This doesn't include server based slots where the theme (the game e.g. Miss Kitty, Joe's Yard Games, Lobstermania) itself can be changed or the percentage can be altered by hour, by day by player. We never used server based slots but all casinos use a casino management system (CMS) backend to track players and awards points if they have a card and I mean each spin each bet per second every second all is captured. Award points for example may be 40:1 dollars:points it's ridiculously bad you end up paying $400 for a $10 t-shirt in the gift shop.

You may find a Paytable and Reel PAR Sheet interesting https://www.google.com/search?safe=off&biw=1920&bih=1050&sit...:

Delphi has a slot tech forum too. Randy Fromm is another big name he runs Slot Tech Magazine. Randy may even read HN, Mr Fromm are you there?

The industry is amazing right now so many acquisitions. Former slot giant IGT (USA) a huge company was bought by Spielo (Canada) but Spielo was bought by Atronic and Atronic (Monaco) was bought by LottoMatica (Italy). Bally bought Shufflemaster and Scientific Games bought Bally.

What's the mirror/prism for? I'm assuming this is a legit game - is it just to make games of Blackjack go faster?

the old way of doing it involved cupping your hand around the card and trying to look at the card discretely. The issue is someone could be standing behind you and get a glimpse.

Not to mention with the old method the dealer would actually see their hole card. Let's say the dealer shows a 10, then when they check, they see they have another 10 as their hole card (face down). The dealer could intentionally or unintentionally give away what their card is, causing someone who normally wouldn't hit on, let's say 17, to take a hit, since the dealer would beat them anyways.

With these little windows, the dealer only see IF they have a blackjack, not the actual card itself.

This happens because the markings for 10s (10, J, Q, K) are all offset slightly to the right. Then the Ace is offset slightly up (the dealer turns it before sliding it into the window).

I use to be a casino dealer.

(edit: typo)

So they can check if they have blackjack without flipping the cards.

Wow how is that not cheating by the house?

It's actually there simply to speed up the game. In blackjack, the house plays by a fixed set of rules: If cards are A, do B, if cards are C, do D. So there is no benefit to the dealer for knowing what his down-cards are. It saves everyone time: If the dealer has blackjack everyone loses anyway so there's no point to having everyone take the time to play that round.

That's not entirely true. Players might (stupidly) still choose to play, including doubling-down and/or splitting. In that case the player would lose more, so the hand should be played out.

It depends on the house rules as to whether that's an option.

You're right, my explanation left that out. It depends on whether the casino believes they will make more money by letting stupid players play or by dealing more hands per hour.

Not exactly. In "European style" blackjack, the dealer does not take a hole card until all hands have been played. House rules then dictate whether the extra money from doubles/splits is returned or taken in the event the dealer eventually draws a blackjack.

Because it gives no advantage to the house. The cards are dealt if the house has blackjack then they have blackjack the prism doesn't change that only allows the dealer to know since dealer blackjack automatically wins against any player hand except blackjack.

Because the rules in a casino about what a dealer does are independent of what the dealer holds.

Because it's the rule and everyone knows about it. You could play the game without this with the exact same rules and the same odds, but it would be much more complicated to settle the bets at the end of the hand.

I never play on a table with an auto shuffler. As a player, the house already has an advantage over you. The auto shuffler means the house always has the same advantage on every hand.

At least with a hand shuffled deck, most humans can't get a perfect shuffle, so the odds of any one hand shift slightly back and forth. If you're good at counting cards, you can find the spots where it is slightly in your favor and bet bigger.

At least, it's more fun for me, because I win a little bit more and also get the fun of practicing counting cards.

It's hard to find the hand shuffled decks though -- they pretty much only have them on high stakes games ($25/hand and up).

The condition you're referring to only occurs on one specific type of shuffler, called a CSM (continuous shuffler machine). These are the kind where the dealer feeds previously discarded cards back into the machine every hand or two, and there is never any pause in the game. CSM's are less common than traditional shuffler machines, where two decks/shoes are used, and one is being shuffled while the other is being played with. Traditional shuffler machines have no bearing on your ability to count cards, as the game is played out exactly as it would be if the dealer were shuffling.

Also, advantage players have found flaws that make certain models of shuffle machines vulnerable to attack. Here's a fascinating example of this from the world's best known advatange player, James Grosjean:

https://mobile.nytimes.com/2016/07/03/magazine/how-advantage...

You're right, the CSM is terrible and is what I was actually referring to. However, I will still try to avoid the traditional machine shufflers since they still get more random shuffles than a hand shuffle which rarely has more than 3 or 4 riffles.

Auto shufflers are all about dealing speed. Hand shuffle at high stakes is about service. It isn't about increasing house edge. In fact house edge will fluctuate so little that when it occurs and you make a max bet you'll be spotted and stopped.

Don't the hand shuffled games modify the payout for blackjack making counting unprofitable?

Lots of casinos are going to 6/5 payouts instead of 3/2, as well as various other restrictions on doubling down or splitting etc, regardless of shuffle method primarily because most tourists don't know any better that they are playing at a higher disadvantage than before, squeezing the margin on card counters is a side benefit.

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