How much EV lost by not doubling?

I have a friend who was playing over his head one day at a blackjack table and found himself with a $2000 bet in front of him, 11 as his total, and the dealer showing a 6. As anyone with a clue can tell you, this is about as good of a doubling situation as it gets. Unfortunately, my friend did not want to risk losing $4000 that hand and hit instead (he drew a ten and won).

I couldn't believe my friend did not double. I told him he cost himself a lot of expected value by hitting instead of doubling, but I'm not exactly sure how much. I haven't found a free tool that can calculate the amount and I haven't been able to do it myself, so I was hoping I could get help here. This happened at Atlantis in Paradise Island, where I believe the rules are six decks, dealer stands S17.

For the record, my friend is a very knowledgeable gambler and he could easily afford to lose an extra $2000 by doubling, which is why I was so surprised by his decision to hit.

Pussy :) Your friend gave up .33 of one bet, or $667 in lost E.V.

Thanks for the response. My somewhat-educated guess would have been $600-$1000. Do you mind sharing how you calculated that number?

Quote: sangaman

For the record, my friend is a very knowledgeable gambler and he could easily afford to lose an extra $2000

But it was the action of a scared, inexperienced gambler. Puzzling..

>I have a friend who was playing over his head one day at a blackjack table
By this do you mean he was playing for more money than he would normally play for or that he was making wagers in a game about which he lacked fundamental knowledge?

>Unfortunately, my friend did not want to risk losing $4000 that hand and hit instead (he drew a ten and won).
If he did not want to risk four-thousand and therefore refused to bet four-thousand, I would say he is a very good gambler.

>I couldn't believe my friend did not double.
Perhaps there was a friend of his watching him and his play was affected by it.
Perhaps the Double or Not is a decision that is mentally "off his radar" and he simply never doubles because its an annoying distraction similar to the darned dealer constantly offering him insurance even though he never takes insurance.

Quote: sangaman

I have a friend who was playing over his head one day at a blackjack table and found himself with a $2000 bet in front of him, 11 as his total, and the dealer showing a 6. As anyone with a clue can tell you, this is about as good of a doubling situation as it gets. Unfortunately, my friend did not want to risk losing $4000 that hand and hit instead (he drew a ten and won).

I couldn't believe my friend did not double. I told him he cost himself a lot of expected value by hitting instead of doubling, but I'm not exactly sure how much. I haven't found a free tool that can calculate the amount and I haven't been able to do it myself, so I was hoping I could get help here. This happened at Atlantis in Paradise Island, where I believe the rules are six decks, dealer stands S17.

For the record, my friend is a very knowledgeable gambler and he could easily afford to lose an extra $2000 by doubling, which is why I was so surprised by his decision to hit.

Knowledgeable in basic strategy, card counting, Kelley Criterion, Risk of Ruin? That was an unbelievable rookie mistake. Too bad he didn't have a "helpful" dealer to coax him into doubling for less.

Doesn't sound like a mistake to me. He wasn't comfortable making another 2k bet. Pretty simple. If I'm playing dollar poker and I see a better opportunity that is at the $2 denom I'm not going to do it if I'm not comfortable with it or have the bankroll even though the EV on that particular game may be better. Did he believe the deck contained too many low cards because you say that he wasn't comfortable doubling on that specific hand. If he was knowledgeable I'm sure he had some sort of count going.

In that case the mistake was betting $2000 in the first place.

.....

If $2000 was his flat bet, then he REALLY should have doubled. After all, doubling an 11 vs 6 is a no brainer. The only time you'd understandably hesitate, is if the bet is significantly more than your standard minimum bet.

.....

Quote: FleaStiff

By this do you mean he was playing for more money than he would normally play for or that he was making wagers in a game about which he lacked fundamental knowledge?

More money than he'd normally play for. The $2000 bet came after a string of $100 bets that resulted in $1000 of losses followed by a $1000 hand that lost. $2000 is significantly more than any wager he'd normally make against a casino.

Quote: FleaStiff

Perhaps the Double or Not is a decision that is mentally "off his radar" and he simply never doubles because its an annoying distraction similar to the darned dealer constantly offering him insurance even though he never takes insurance.

He understands basic blackjack strategy so it didn't have to do with something silly like never doubling or some superstition.

Quote: benbakdoff

Knowledgeable in basic strategy, card counting, Kelley Criterion, Risk of Ruin? That was an unbelievable rookie mistake. Too bad he didn't have a "helpful" dealer to coax him into doubling for less.

He's knowledgeable in understanding of probability, variance, and expected value - and he's a world class poker player - but not particularly experienced with casino games like blackjack. He's not a counter or advantage player or anything.

I heard this anecdote from him while we were exchanging stories about the dumbest/most embarrassing gambling decisions we've ever made. I understand (but don't condone) the desire to recover his blackjack losses, but I still can't understand getting to that point and then passing on a hugely +EV opportunity only to reduce variance. Wasn't the whole point of betting $2000 in the first place to increase variance and give himself a shot at getting even quickly? Like I said, losing $4000 on that hand wouldn't have been fun, but it would have hardly put a dent in his bankroll. Chalk it up dumb things we all do sometimes, I guess.

Quote: benbakdoff

In that case the mistake was betting $2000 in the first place.

I definitely agree, that was his biggest mistake, especially if he refuses to split or double because that sharply increases house edge. I made this thread mainly to see how one could calculate how much $EV he lost by hitting instead of doubling.

Quote: FleaStiff

>

>Unfortunately, my friend did not want to risk losing $4000 that hand and hit instead (he drew a ten and won).
If he did not want to risk four-thousand and therefore refused to bet four-thousand, I would say he is a very good gambler.

I would disagree. I would say he is a horrible gambler. Anyone who would make a blackjack bet without the wherewithall to cover necessary doubles or splits is competing without the full value of the rules of the game and is therefore a fool.

Quote: SOOPOO

I would disagree. I would say he is a horrible gambler. Anyone who would make a blackjack bet without the wherewithall to cover necessary doubles or splits is competing without the full value of the rules of the game and is therefore a fool.

I agree he was a horrible gambler at that particular blackjack table - it's obviously a huge mistake to bet an amount so big that it'll make you hit an 11 against a 6. However, I think it's too harsh to characterize him as a horrible gambler because of one foolish binge. My friend is very intelligent and has won a lot of money playing poker. I think (almost) everyone has made mistakes at some point due to inexperience/emotions. Maybe there should be a thread for stupid/reckless gambling confessions...

As I said I'm mostly interested in calculating his EV loss from hitting. How does one get to $667 if that is the answer?

The difference between the values in two of the tables found here:

WOO - BJa1

11 vs 6 hit EV = .3337
11 vs 6 dbl EV = .6674

difference is .3337 * 2000 = $667

(NOTE: since you won't hit again if you hit 11 vs 6, it is no coincidence that the dbl EV is exactly twice the hit EV)

Quote: SOOPOO

I would disagree. I would say he is a horrible gambler. Anyone who would make a blackjack bet without the wherewithall to cover necessary doubles or splits is competing without the full value of the rules of the game and is therefore a fool.

Not really. Being unable to take full advantage of the rules and options involved in your wager is unwise, but the over-riding rule is do not wager more than you are comfortable wagering. So despite some impractical decisions he may have made in his wagers, when he was confronted with the situation of putting up another two grand and he did not do so, he followed the primary rule of any gambler: do not wager more than you are truly comfortable wagering. He had been unwise but when it came time to up the ante he refused to do so and that is the hallmark of a good gambler. He accepted some slicing and dicing of his chances but he followed the over-riding rule of money management.

Quote: dwheatley

The difference between the values in two of the tables found here:

WOO - BJa1

11 vs 6 hit EV = .3337
11 vs 6 dbl EV = .6674

difference is .3337 * 2000 = $667

(NOTE: since you won't hit again if you hit 11 vs 6, it is no coincidence that the dbl EV is exactly twice the hit EV)

Thanks, this is exactly what I was looking for. I tried to find a table like that on my own but couldn't.

Quote: FleaStiff

Not really. Being unable to take full advantage of the rules and options involved in your wager is unwise, but the over-riding rule is do not wager more than you are comfortable wagering. So despite some impractical decisions he may have made in his wagers, when he was confronted with the situation of putting up another two grand and he did not do so, he followed the primary rule of any gambler: do not wager more than you are truly comfortable wagering. He had been unwise but when it came time to up the ante he refused to do so and that is the hallmark of a good gambler. He accepted some slicing and dicing of his chances but he followed the over-riding rule of money management.

We can agree to disagree, but once he made the bet it is implied that he is risking the maximum that a reasonable use of the rules allow. Back in the day when I played BJ I would never bet unless I had enough for one split and 2 subsequent doubles. So if I had $100 my max bet would be $25. Having once seen someone on their 'last bet' not be able to split 8's against a bust card was painful.

The informed blackjack player should understand that there is always the potential for the original bet to become 8 units with splitting and doubling after the splits. I know of at least one very major casino that allows unlimited splitting and these big hands happen more often than one would think.

What would the player have done if he was dealt 2,2? Hit? Sangaman, I'd love to know what your friend's bankroll was if it's not too personal.

Quote: benbakdoff

The informed blackjack player should understand that there is always the potential for the original bet to become 8 units with splitting and doubling after the splits. I know of at least one very major casino that allows unlimited splitting and these big hands happen more often than one would think.

What would the player have done if he was dealt 2,2? Hit? Sangaman, I'd love to know what your friend's bankroll was if it's not too personal.

I agree. I remarked that my friend could have just made $1000 bets until he was either back to even or down another $2000 (at which point I would hope he'd quit), that way he can at least double or split once and can still get even quickly. As it turned out, he would've just doubled his 11 for another $1000 and gotten even just as quickly.

I went back and asked my friend what he would have done with 22, and he said he'd have hit. However, he also explained that he'd bet almost all the chips he had on him in making that $2000 bet, and he didn't know he could double for less. I thought he could've at least borrowed from his friend he was playing with, but it turns out the both of them were playing that blackjack table with the same chips. If he wanted to double for full, he would've needed to run to his hotel room or an ATM which would have taken at least several minutes. I don't know how casinos handle these situations and whether or not they would have held the table for him (doubtful) or extended him credit.

Anyway, it turns out my friend didn't chicken out of doubling so much as he made a silly BJ wager that he couldn't double or split, and it wound up costing him. I didn't get all the details right the first time around apparently, but the $EV loss was the same. I don't know for sure what his bankroll is but it's at least several $100k. I'm sure the Kelly Criterion would have strongly advocated doubling.

$680.

The odds will vary with the exact situation (# decks, cards seen, etc).
6 decks S17, no prior hands, heads up, you have a 7+4, dealer showing 6.
Hit = has an EV of +34% ($2k bet, EV+680)
Double = has an EV of +68% ($2k bet, EV+1360)
Stand (just to be complete) = EV -15%
Surrender = EV -50%

Quote: sangaman

Thanks, this is exactly what I was looking for. I tried to find a table like that on my own but couldn't.

Wizard of Odds Appendix 9

The precise value would depend on the constituent cards that make up his 11, how many decks there are, and the rules (like is the dealer required to hit a soft 17).

It is possible to rank order the (improved EV) of a move. For instance, of all the plays where the recommendation is to DOUBLE, the case of 11 vs 6 is the strongest at $667 over the decision to hit. The case of A,2 against a dealer 5 has an improved EV of about $5 (on $2K bet) on DOUBLE vs HIT.

So if your friend was nervous about putting that much money on the table, he choose the strongest possible hand to ignore the suggest strategy.

Quote: EvenBob

But it was the action of a scared, inexperienced gambler. Puzzling..

When Mohegan Sun casino had their triple down promotion, making their BJ tables +EV, I never bet more than $20, and I did not stay there the whole night the promotion was on.
Does it make me a "scared, inexperienced gambler" as well? I mean, I obviously "lost some EV" by betting $20 instead of $500, and gave up some more by leaving early ...
I don't see any difference with the double down situation.