Nareed
Joined: Nov 11, 2009
• Posts: 11413
November 20th, 2009 at 8:15:41 AM permalink
Games like craps are made up of independent events. That is, no roll of the dice affects the odds of subsequent rolls. No number is "due." The odds that any number will turn up are the same for every roll (not the same for every number).

In games like blackjack the events are not independent. If certain cards have been played then certain cards remain, therefore the cards played affect the odds of subsequent hands (this doesn't apply if you shuffle the deck after every hand).

Let's take a simple example. You have a standard deck of 52 cards, shuffled randomly. The odds you'll draw an ace are 4 in 52, given there are 4 aces in the deck. Suppose you draw the first card and it's an ace. Now the odds for another ace are 3 in 51, but the odds for all other cards are 4 in 51 (I know this isn't mathematically precise. I'm not good at practical amth, but I've some grasp of the theory).

Therefore if you can keep track of the cards dealt, you can estimate the odds for the cards left with a great degree of precision, until the cards run out and the deck is shuffled. That's the explanation for card counting.

Now, how do you actually count the cards? That I know little about. The classic explanation is this: you begin at zero and count like this:

aces, tens and face cards are worth minus one
the cards between twoa nd six (if memory serves) are worth one
all other cards (seven eight and nine) are worth zero.

So if the delaer dealt the following: A-5, 2-3, your count would be 0-1+1+1+1=2

This tells you lower ranked cards are now somewhat less likely than higher ranked cards. And that's as far as my understanding, such as it is, of card counting goes (and no doubt I have some of it wrong). Oh, suits are not considered since they don't affect the outcome.

So, yes, this is a fact: card counting does give the player information about the state of the deck and a better estimate of the shifting odds. This can translate into an advantage for the player.

But simple as it sounds it's not really that simple. My example is very elementary and lacks any information about basic strategy. Also most people can't so simple math in their head, even these easy additions and substractions (I can't).

Also casinos ahve taken measures against card coutners: multiple decks, continous shuffling, burn cards, cut cards, and I'm told dealers keep an eye for changing bets that would indicate a card counter.

Counting cards is a skill, not cheating and, as far as I know, it's not illegal. But the casinos can prevent you from playing blackjack if they think you're counting cards (or counting cards well).

The advantage the player gets is substantial but not overwhelming. He won't win every hand, and he won't walk out with millions in every session. Still, card coutners can make a living playing BJ.
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boymimbo
Joined: Nov 12, 2009
• Posts: 5994
November 20th, 2009 at 9:02:30 AM permalink
There are lots of systems to counting cards. You are looking essentially for a differential between the face cards and small cards in the deck. And yes, you literally look at the cards coming out and subtract the big from the small. Divide the difference by the number of cards remaining (usually expressed in decks) to get a "true count". It's actually a fairly easy skill to acquire.

The more face cards available, the better it is for the player. Why? First there are more blackjacks available and you get paid at 1.5 to one. Second, the availability of less small cards make it more difficult for the dealer to make a hand when dealt anything less than 17. The converse is true when there are more small cards available.

Because you know that there are more or less face cards available, you can adjust strategy and bet more or less accordingly.
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Nareed
Joined: Nov 11, 2009
• Posts: 11413
November 20th, 2009 at 9:49:47 AM permalink
Quote: boymimbo

There are lots of systems to counting cards. You are looking essentially for a differential between the face cards and small cards in the deck. And yes, you literally look at the cards coming out and subtract the big from the small. Divide the difference by the number of cards remaining (usually expressed in decks) to get a "true count". It's actually a fairly easy skill to acquire.

I've never tried it at a casino. I've tried counting agasint computer simulations, where I've full control of the number of players. I fail misserably each time. I quickly loose count or get confused. I've also tried dealing cards to myself and counting. Not very well, either.
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marksolberg
Joined: Nov 14, 2009
• Posts: 205
November 20th, 2009 at 10:24:29 AM permalink
I work at a casino and we don't sweat counters. Counters, or at least the ones that come to our joint are pretty easy to recognize. When we get a counter we let them play and watch them closely. Our table limits are such that we won't get hurt significantly in the short term. We stick with our table limits. We won't increase limits upon request. Just because you're a counter does mean you are going to win. In fact more often than not they end up with the same results as non-counters. Now to be honest, if we had a good counter that attempted to play on a regular basis we would probably back them off in one way or another. I'm sure you're thinking that we probably just don't recognize the good counters and we get hit more often than we think but that's unlikely given our familiarity with our customers.

Due to television and movies there's this perception that counting is a sure fire, win every time way to make big money. If it was I'd probably be trying it myself.
Nareed
Joined: Nov 11, 2009
• Posts: 11413
November 20th, 2009 at 10:45:13 AM permalink
Quote: marksolberg

Due to television and movies there's this perception that counting is a sure fire, win every time way to make big money. If it was I'd probably be trying it myself.

Of course. But reasonable people know that movies and TV exaggerate and simplify everything, when they don't outright make things up. And this caveat should also apply to documentaries.

So, any hints as to what your casino is?
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marksolberg
Joined: Nov 14, 2009
• Posts: 205
November 20th, 2009 at 12:57:25 PM permalink
I work at a Tribal casino in northern Michigan. Wouldn't take too much detective work to figure out which one.
Nareed
Joined: Nov 11, 2009
• Posts: 11413
November 20th, 2009 at 1:53:35 PM permalink
Quote: marksolberg

I work at a Tribal casino in northern Michigan. Wouldn't take too much detective work to figure out which one.

Thanks. Let's just say my odds of ever going to Michigan are really small :)

Of course, you never know. I once nearly got sent to Minneapolis to meet a suplier.
Donald Trump is a fucking criminal