Recommend
3 
 Thumb up
 Hide
15 Posts

BoardGameGeek» Forums » Board Game Design » Design Theory

Subject: Why card counting in Blackjack is not allowed. rss

Your Tags: Add tags
Popular Tags: [View All]
guy
Wallis and Futuna
Grand Bois Du Nord
msg tools
Avatar
mbmbmbmbmb
You guys analyze and design games, so you can probably follow my reasoning here:

If you've ever tried to play 21 with your friends, you realized so-called "card counting" means the dealer is at a disadvantage toward the end of the deck. Once a player knows that the face cards have been rare and there's going to be lots more (or the opposite), he bets accordingly.

Professional gaming locations, where these things mean real money, do 2 things to mitigate the problem:

1) Add decks to the shoe (the pile of undealt cards). Many casinos use a 7-deck shoe. This reduces the advantage of the player at each card count increment. In fact, the formula for how the probabilities change at each face card revealed includes the number of decks in the denominator--more decks mean a smaller shift and thus a smaller advantage to the card-counter.

2) Make card-counting against the rules.


But this is a silly situation. Since it is obvious that there is a mathematically certain way to reduce the advantage to as small as the casino would like, there is no real reason for solution #2 above.

That is to say, in my casino, I could confidently post a screen at each table that would show every card that had so far been revealed in the game (dead cards would be scanned after each individual played out his hand). The dealer's cards would be scanned after each round. I'd invite card counters.

Then I'd deal 52 cards out of a 10-deck shoe before retiring the shoe (to be emptied, shuffled, and repacked--there are high-speed machines to do such). Count all you want, at no time is your advantage greater than the dealer's. By adding more decks, but still only dealing out one, card-counting advantage can be reduced to as small as you'd like.


But then it occurs to me that there probably are people who know probability who work for casinos (imagine!). So how have they not noticed this problem can be solved without counting bans?

Ohhhhhhhhh. Duh. Now it is obvious to me. They WANT that rule on the books because that gives them an excuse to throw out anyone they choose. Of course, they can do that anyway (casinos are private property--if they ask you to leave you must), but what excuse could they use? Without quoting a broken rule, players would stop visiting a casino that threw out patrons for no reason.

Or maybe this rule was written just so the casinos could save some wear and tear on their oft-shuffled decks! Yikes!
1 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Alex Singh
United States
Moreno Valley
CA
flag msg tools
badge
Avatar
mbmbmbmbmb
Casinos want players who think they can count cards to play. They don't want players who can actually count cards to play. Having the rule allows them to keep the former and ban the latter.
2 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Jeremy Lennert
United States
California
flag msg tools
designer
Avatar
mbmbmbmbmb
Back when scholars first figured out that it was possible to gain an advantage over the dealer by counting cards, the casinos' first plan was to simply stop offering the game--just like they wouldn't offer any other game where it's possible to gain an advantage over the house.

But then they noticed that Blackjack had suddenly become incredibly popular...and that for every person who could actually count cards, there were many people who thought they could count cards. So, rather than retiring the game, they decided they could make more money by encouraging the perception that you could beat the house (while throwing out anyone who actually can).
7 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Joe Salamone
United States
Billerica
Massachusetts
flag msg tools
badge
Aggravating people worldwide since 1964
Avatar
mbmbmbmbmb
A lot of casinos also added ludicrous side-bets to their Blackjack tables. Just wager an additional dollar and you can win $XXXX if the dealer deals three 7s in a row or whatever. So, the players just lose an extra dollar on every hand and once in a great while, someone wins. I never ante the extra dollar and some other players are astonished. "Don't you want to win the big jackpot?" I once calculated the odds of winning one of these side bets. I think the odds were something like 85,000:1 to win $5,000. I mentioned this to someone at the table who was encouraging me to kick in the extra buck, but she didn't want to hear it (or maybe she didn't believe me). She was probably counting cards, too.
2 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Bill Eldard
United States
Burke
Virginia
flag msg tools
mbmbmbmbmb
professorguy wrote:
1) Add decks to the shoe (the pile of undealt cards). Many casinos use a 7-deck shoe. This does 2 things: It reduces the advantage of the player at each card count increment. In fact, the formula for how the probabilities change at each face card revealed includes the number of decks in the denominator--more decks mean a smaller shift and thus a smaller advantage to the card-counter. .. .


And the dealer will get a new shoe when only half of the 7/8-deck shoe is exhausted.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Christopher Dearlove
United Kingdom
Chelmsford
Essex
flag msg tools
SoRCon 8 27 Feb - 1 Mar 2015 Basildon UK http://www.sorcon.co.uk Essex Games 27 Jul '15
badge
Avatar
mbmbmbmbmb
I thought there was a case that established that you can't make card counting banned, so any gains established that way are legal, but you can ban someone who you even suspect of doing it. And you can make collusion between players illegal, and you need collusion to make it practical (counter playing for small stakes, move in second player with big stakes when tipped that the deck is good - because an individual changing stakes is too obvious).

Anyone with real information, open to correction.

But why doesn't the casino simply count cards itself, and shuffle when at a disadvantage? With computer aid (banned for players, but not as far as I know for the house) it could be pretty effective. It could do the whole image recognition, counting (however clever an algorithm you like, more sophisticated than a player could manage) and just indicate to the dealer time to reshuffle. Any legal or practical problem? (PR problem maybe, so don't advertise doing it).
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
John duBois
United States
Troy
Michigan
flag msg tools
designer
badge
Avatar
mbmbmbmbmb
Atlantic City casinos can't ban card counting after the NJ Supreme Court's Uston vs Resorts International Hotel decision. They can merely make it very difficult.

The New Jersey Casino Control Commission can ban card counting, but they haven't.

Elsewhere, card counting is not illegal, but many casinos disallow it.
1 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Catherine von Xlorp
United States
San Jose
California
flag msg tools
Sly like a duck
badge
Try the biscuits
Avatar
mbmbmbmbmb
Wouldn't the casino have its own computers tracking all cards played as a database for all sorts of counter-measure fun?

Among other things they could make their own algorithms for optimal play based on data revealed to that point. It would be easy enough to see correlations in betting patterns from a card counter or schemer wearing sheep's clothing at the table.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Metäl Warrior
Netherlands
flag msg tools
mbmbmb
xlorp wrote:
Among other things they could make their own algorithms for optimal play based on data revealed to that point.


House/dealer has pre-determined rules on how they play, and changing them would make the game into something else than blackjack.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Jeremy Lennert
United States
California
flag msg tools
designer
Avatar
mbmbmbmbmb
Jaffeli wrote:
xlorp wrote:
Among other things they could make their own algorithms for optimal play based on data revealed to that point.


House/dealer has pre-determined rules on how they play, and changing them would make the game into something else than blackjack.

I believe xlorp meant they could calculate optimal play for their customers, and then use that knowledge to kick out those customers who actually play optimally.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Greg Case
Canada
Waterloo
Ontario
flag msg tools
mbmbmbmbmb
This is an interesting (and related) article

http://www.theatlantic.com/magazine/archive/2012/04/the-man-...

 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
guy
Wallis and Futuna
Grand Bois Du Nord
msg tools
Avatar
mbmbmbmbmb
Jaffeli wrote:
House/dealer has pre-determined rules on how they play, and changing them would make the game into something else than blackjack.

Yes. I've played in casinos where the rules the dealer had to follow were printed on the cloth ("Dealer stands on 17") and the game was played with all cards face up. Since the dealer had no choices, him knowing your hand made no difference.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
charlie yu
Hong Kong
flag msg tools
JohnduBois wrote:
Atlantic City casinos can't ban card counting after the NJ Supreme Court's Uston vs Resorts International Hotel decision. They can merely make it very difficult.

The New Jersey Casino Control Commission can ban card counting, but they haven't.

Elsewhere, card counting is not illegal, but many casinos disallow it.

They don't kick you for counting, they kick you for undisclosed reasons.
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Graham Robinson
United Kingdom
flag msg tools
badge
In memory of Tara, my beloved Wolfhound-Deerhound cross. Flew away Feb 2016, still missed.
Avatar
mbmbmbmbmb
Many casinos hire dealers who can card count, and change the shoe if there's an advantage to the players...
 
 Thumb up
 tip
 Hide
  • [+] Dice rolls
Front Page | Welcome | Contact | Privacy Policy | Terms of Service | Advertise | Support BGG | Feeds RSS
Geekdo, BoardGameGeek, the Geekdo logo, and the BoardGameGeek logo are trademarks of BoardGameGeek, LLC.