BlkJkPlyr
BlkJkPlyr
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December 30th, 2014 at 6:42:38 PM permalink
I'd like to get a sanity check on my calculations here.

I understand the dangers in progressively increasing your bets with each loss in the hopes of recouping losses after a predetermined number of hands. But after looking at the numbers, I think there may be a case for using this tactic as a tool perhaps as a last-ditch desperate measure. I'm not suggesting playing like this in general.

Let's say for example, you're playing $25 min hands with a max bet of $300 and have a bankroll of $700 - $1000.

With proper Basic Strategy, you're looking at winning about 48% of hands, losing about 52% (in general).

Using a sequence of six hands, starting with a min. $25, let's say you lose the first hand. The second hand, instead of doubling, you bet another $25. If you win, this brings you back to the original amount, essentially turning the previous loss into a push (better than a loss, and the sequence ends there). If you lose the second hand, you start doubling your bets from that point through the sixth hand. At the sixth hand, (since we did not double the first losing hand) we would be at a bet of $400. The max bet for the game however, is $300. So, the sixth hand gets a bet of $300 instead of $400. Any win out of the first 5 hands would improve your situation essentially from a loss to a push. Losing 5 straight and winning the 6th hand that we bet $300 on, would put you at -$100 for the sequence, as opposed to the -$150 loss you would have sustained if you lost the previous 5 hands in a row at the min. $25 (-$100 is still better than -$150). It gets hairy from the 7th hand on in that positive affects from the max $300 dwindles drastically from there.

Now, my question regarding my calculations is this...

At a 52% chance of losing each hand, the odds of losing six in a row are about 0.02% Correct? So, from a mathematical standpoint, if you have a 99.98% chance of improving your situation by using a six-hand sequence of negative progression bets, why is this a bad gamble to make? I understand the 0.02% probability of losing the whole $700 spent in the sequence if you lose all six hands... But that's why it's called gambling, right? And if you have the bankroll to cover it, and stop at a determined number of hands (in this example, six hands) and it's only used when you have dipped past your winnings, etc. maybe it wouldn't be such a bad tactic?

I'm interested in what y'all think. Thanks!
BlkJkPlyr
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December 30th, 2014 at 9:31:32 PM permalink
Or, in cases where you can't get a true count, such as online casinos where decks are shuffled after each hand, would it make sense to rely on probability of maintaining a losing/winning streak as a tell as to when to raise/lower your bets?

Not as a "hunch" or being "due for a win or loss" but following the mathematical probability of continuing to win/lose hands.
thecesspit
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December 31st, 2014 at 12:46:56 AM permalink
Six hands in a row lost is a 2% chance not 0.02%.

As for your second point, the chance of continuing the streak is 52% each time. Given your number of winning a hand of BJ being 48%, which I am pretty sure is wrong.
"Then you can admire the real gambler, who has neither eaten, slept, thought nor lived, he has so smarted under the scourge of his martingale, so suffered on the rack of his desire for a coup at trente-et-quarante" - Honore de Balzac, 1829
sodawater
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December 31st, 2014 at 1:23:58 AM permalink
every bet you make is subject to the house edge, whether it's part of a progression or not.

think of the house edge as a tax applied to every single bet made, regardless of the bet's outcome.

if you're a basic strategy player, blackjack is a negative game.

hence the more you bet, the more you will lose.

if you have a 1% disadvantage, you will lose 12.5 cents every time you bet $25. every time you bet $300, you will lose $3.

that's all you need to know. you don't need to calculate the odds of losing n hands in a row -- you lose every hand you make a bet, in an amount equal to the house edge times your bet.
OnceDear
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December 31st, 2014 at 1:30:51 AM permalink
Quote: BlkJkPlyr

I'd like to get a sanity check on my calculations here.

I understand the dangers.... But after looking at the numbers, I think there may be a case for using this tactic as a tool perhaps as a last-ditch desperate measure.

What constitutes desperate? Maybe that despair that you feel after losing a succession of hands? Think how desperate you feel after doubling up to the last of your bankroll and losing again, then maybe pushing your luck, visiting the ATM and doubling again, only to lose yet again!
Quote: BlkJkPlyr

With proper Basic Strategy, you're looking at winning about 48% of hands, losing about 52% (in general).


Check those numbers: More like 42% win, 8% push and 49% lose. Ignoring pushes, about 46% win, 54% lose. https://wizardofodds.com/games/blackjack/appendix/4/ Some of those wins pay 3:2 which messes with the numbers, of course. But that doesn't mess with the probability of the losing streak that you describe.
Quote:

Using a sequence of six hands... Losing 5 straight and winning the 6th hand that we bet $300 on, would put you at -$100 for the sequence, as opposed to the -$150 loss you would have sustained if you lost the previous 5 hands in a row at the min. $25 (-$100 is still better than -$150). It gets hairy from the 7th hand on in that positive affects from the max $300 dwindles drastically from there.

. Therefore Martingale must be good? Hmmm. Lose that 7th instead of winning it and you are $700 down, where flat betting $25 would have put you $175 down. You are being selective when you look at the potential scenarios.

Looking at a realistic scenario (been there, got the t-shirt) When you have doubled up many times and your bankroll is almost depleted, you might very well get a hand that needs splitting or doubling several times. Then you are faced with either playing bad strategy or with finding lots more money to raise your bet, and your risk, to many times over. What do you do then?

Now, my question regarding my calculations is this...

Quote:

At a 52% chance of losing each hand, the odds of losing six in a row are about 0.02% Correct?


At a 53.64% chance of losing each hand, the odds of losing six in a row are about 2.39%. The odds of that 6th hand losing are about 53%, after the previous 5 are history.

Quote:

So, from a mathematical standpoint, if you have a 99.98% chance of improving your situation

97.61% ! Your are only improving the situation from before playing any hands. Once you start bringing your progression into play, you are already in a hole and digging. Losing any 7 consecutive hands in a roll becomes very likely in a very small session.
Quote:

But that's why it's called gambling, right? And if you have the bankroll to cover it, and stop at a determined number of hands (in this example, six hands) and it's only used when you have dipped past your winnings, etc. maybe it wouldn't be such a bad tactic?

Maybe if you can completely negate human nature and not chase those HUGE losses.
Martingale can be a fun system, giving massive adrenaline rushes, just like russian roulette.
Psalm 25:16 Turn to me and be gracious to me, for I am lonely and afflicted. Proverbs 18:2 A fool finds no satisfaction in trying to understand, for he would rather express his own opinion.
BlkJkPlyr
BlkJkPlyr
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December 31st, 2014 at 2:24:17 AM permalink
Thanks for the correction on the 2%. I was slso using general percentages for the house edge. I know using proper basic strategy, you can get close to 50/50. So, 52/48 was just a generality.

I'm confused about your answer though. As you point out, (given a house edge of 2%), the odds of losing six in a row is 2%. So, it stands to reason that after losing 5, you should have a 98% chance of winning the sixth hand (in general). Then you said the odds are 52% each hand for the trend continuing.

Or, rather the probability of each hand losing would be 52% for each hand, but the likelihood of the result continually falling within that 52% six times in a row, is 2%. On the sixth hand, all things being equal, you'd have a 98% chance of the result falling somewhere in the 48% range. That's how in viewing it. What am I missing?

Thanks!
OnceDear
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December 31st, 2014 at 3:13:46 AM permalink
Quote: BlkJkPlyr

I'm confused about your answer though. As you point out, (given a house edge of 2%), the odds of losing six in a row is 2%. So, it stands to reason that after losing 5, you should have a 98% chance of winning the sixth hand (in general). Then you said the odds are 52% each hand for the trend continuing.

Or, rather the probability of each hand losing would be 52% for each hand, but the likelihood of the result continually falling within that 52% six times in a row, is 2%. On the sixth hand, all things being equal, you'd have a 98% chance of the result falling somewhere in the 48% range. That's how in viewing it. What am I missing?
Thanks!



OK. Sit at a table not having played any hands, or indeed having played any number of hands. The chance of losing the next 6 hands in a row is indeed about 2% (actually less). You are in a good place with a good bankroll. The chance of losing the next hand is 52%. Proceed to lose that hand. The probability that you just lost that hand is not 52% any more, it is 100%, because you did! Proceed to lose another 5 hands in a row: The probability that you just lost those 6 hands started out as slim, but now it has happened and the probability that you are where you are is 100%. The probability of you losing the next hand is again 52%. Fate shows no mercy. There is no God of probability that says you are more likely to win the next hand than you are to win any hand, just because you had a losing streak. Before you started playing, you could have been confident that you had only a 2% chance of getting in this situation over the single set of 6 hands. But once you had those few losing hands, your probability of having loser number 7 became more and more.

In a real life game, you will have a mix of wins and losses, sometimes one at a time, sometimes two, three, four, five... Play a few hundreds or thousands of hands and you will see approximately half as many 'streaks' of 2 losing hands as you do streaks of 1; half as many streaks of 7 losing hands as 6 etc. You WILL see lots of streaks of 7 losing hands, but fortunately for you, you lost your entire bankroll on the first one you saw.
Psalm 25:16 Turn to me and be gracious to me, for I am lonely and afflicted. Proverbs 18:2 A fool finds no satisfaction in trying to understand, for he would rather express his own opinion.
onenickelmiracle
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December 31st, 2014 at 6:08:42 AM permalink
It's as simple as gambling. You get lucky or you don't. Nothing can be proven to work for the long term when already proven to not work. You're better off not gambling and finding another way to get the money. If it's an impossible amount, you can try if you're desperate but don't convince yourself there is a way to produce miracles at will.
I am a robot.
Donuts
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December 31st, 2014 at 7:55:00 AM permalink
This isn't intuitive to most people, but winrate of hands for blackjack is relatively low at only 42% roughly. You will another 48% of hands and push the rest.
http://www.blackjackincolor.com/truecount5.htm

The reason this is possible is because of the player advantage gained from the ability to double down, split, and receive 3:2 on BJ. Without this the house edge would be enormous.

I'm not a fan of progressions, but I'd probably play baccarat over blackjack if I was going to use one since working double downs and a subpar hand winrate into your system is just extra effort.
AxelWolf
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December 31st, 2014 at 8:46:58 AM permalink
Quote: Donuts

This isn't intuitive to most people, but winrate of hands for blackjack is relatively low at only 42% roughly. You will another 48% of hands and push the rest.
http://www.blackjackincolor.com/truecount5.htm

The reason this is possible is because of the player advantage gained from the ability to double down, split, and receive 3:2 on BJ. Without this the house edge would be enormous.

I'm not a fan of progressions, but I'd probably play baccarat over blackjack if I was going to use one since working double downs and a subpar hand winrate into your system is just extra effort.

but since Double downs are oftentimes a strong play this could really pump you up.

Imagine being at a high level and getting an 11 vs a 6
♪♪Now you swear and kick and beg us That you're not a gamblin' man Then you find you're back in Vegas With a handle in your hand♪♪ Your black cards can make you money So you hide them when you're able In the land of casinos and money You must put them on the table♪♪ You go back Jack do it again roulette wheels turinin' 'round and 'round♪♪ You go back Jack do it again♪♪
Dieter
Administrator
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December 31st, 2014 at 9:06:11 AM permalink
Quote: BlkJkPlyr

it stands to reason that after losing 5, you should have a 98% chance of winning the sixth hand (in general).



You are never due for a win.

Go read up on the Gambler's Fallacy.
May the cards fall in your favor.
Donuts
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December 31st, 2014 at 9:59:16 AM permalink
Doublepost (below)
VVVVVVVVVVVVV
Donuts
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December 31st, 2014 at 10:00:05 AM permalink
Quote: AxelWolf

but since Double downs are oftentimes a strong play this could really pump you up.

Imagine being at a high level and getting an 11 vs a 6



Or you double your 11v6 at your progression max and get #rekt.
thecesspit
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December 31st, 2014 at 10:04:40 AM permalink
Quote: BlkJkPlyr

Thanks for the correction on the 2%. I was slso using general percentages for the house edge. I know using proper basic strategy, you can get close to 50/50. So, 52/48 was just a generality.

I'm confused about your answer though. As you point out, (given a house edge of 2%), the odds of losing six in a row is 2%. So, it stands to reason that after losing 5, you should have a 98% chance of winning the sixth hand (in general). Then you said the odds are 52% each hand for the trend continuing.



Nope, it doesn't stand to reason at all. The 98% chance is starting from 0 losses to lose the next 6. NOT from losing 5 in a row to losing 6 in a row.

Quote:

Or, rather the probability of each hand losing would be 52% for each hand, but the likelihood of the result continually falling within that 52% six times in a row, is 2%. On the sixth hand, all things being equal, you'd have a 98% chance of the result falling somewhere in the 48% range. That's how in viewing it. What am I missing?

Thanks!



Each hand is an Independent event (not quite true in Blackjack, mind, but good enough for a hand waving approximation here). Each hand has a 52% chance of losing (say)... that means 6 hands in a row is a 2% chance. This is a derived effect of the 52% chance, so you can then say 'well 5 in a row loses means I am due a win!'.
"Then you can admire the real gambler, who has neither eaten, slept, thought nor lived, he has so smarted under the scourge of his martingale, so suffered on the rack of his desire for a coup at trente-et-quarante" - Honore de Balzac, 1829
AxelWolf
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December 31st, 2014 at 2:54:56 PM permalink
Quote: Donuts

Or you double your 11v6 at your progression max and get #rekt.

If someone doesn't want a large bet out with a great chance at winning, why have a dumb system in the first place.

Isn't the goal of a system to win money? The best chance you have at winning with a betting system is a situation like I described.

If you don't like or can't handle doubling 11 vs a 6 you should GO HOME. Your face should light up like you just won a jackpot when you get an 11 vs the dealers 6

I know, I know.... someone is going to tell a story how they lost 30 str8 double downs vs 5 and 6 in a row.

Something like this....
I had an Asian dealer once. I had to split 8 times and got a 10 or 11 on each had, I doubled down on each hand, the dealer had a 5 up, turns over a ten... hits gets an ace ...hits again and bingo gets a 5 for 21
♪♪Now you swear and kick and beg us That you're not a gamblin' man Then you find you're back in Vegas With a handle in your hand♪♪ Your black cards can make you money So you hide them when you're able In the land of casinos and money You must put them on the table♪♪ You go back Jack do it again roulette wheels turinin' 'round and 'round♪♪ You go back Jack do it again♪♪
BlkJkPlyr
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December 31st, 2014 at 3:44:52 PM permalink
Quote: thecesspit

Nope, it doesn't stand to reason at all. The 98% chance is starting from 0 losses to lose the next 6. NOT from losing 5 in a row to losing 6 in a row.



Each hand is an Independent event (not quite true in Blackjack, mind, but good enough for a hand waving approximation here). Each hand has a 52% chance of losing (say)... that means 6 hands in a row is a 2% chance. This is a derived effect of the 52% chance, so you can then say 'well 5 in a row loses means I am due a win!'.



If you're flipping a coin six times, and heads were winners and tails were losers, you would have a 2% chance of all six individual events being all winners or all six individual events being all losers.

In my mindset, that relates to the topic at hand because in a negative progression sequence, you only need one winner out of say, 6 (for this example) to be successful. From the beginning of the sequence (starting at 0) you have about a 2% chance of all six events being losers. So, that leaves you with a 98% chance that at least one out of the next 6 events would be a winner (which is all you'd need), starting from 0.
Sonuvabish
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December 31st, 2014 at 3:58:33 PM permalink
Let me just summarize the thread.

I don't understand math, nor am I capable of making simple computations. Why on earth is it a bad idea that I invest a great deal of money into gambling, and why shouldn't I expect to win?
BlkJkPlyr
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December 31st, 2014 at 7:35:56 PM permalink
Ok. Thanks for the help everyone.
thecesspit
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December 31st, 2014 at 8:21:59 PM permalink
Quote: BlkJkPlyr

If you're flipping a coin six times, and heads were winners and tails were losers, you would have a 2% chance of all six individual events being all winners or all six individual events being all losers.

In my mindset, that relates to the topic at hand because in a negative progression sequence, you only need one winner out of say, 6 (for this example) to be successful. From the beginning of the sequence (starting at 0) you have about a 2% chance of all six events being losers. So, that leaves you with a 98% chance that at least one out of the next 6 events would be a winner (which is all you'd need), starting from 0.




Correct. But when you have 5 losers, your chance of the next one being a loser is 52%.

If you do the math, you'll see the expectation of this method is still negative. 2% chances, done several tens or hundreds of times.... multiply up. Your chance of failing in two runs is 1 - .98 X .98 = 4%. For hundred times, it's about 86% chance you'l have at least one failed run.

If you -gotta- make $25 from your $600 bank roll, yeah, betting the minimum to make that profit each time makes sense. But it's not the path to positive expectation. Your expectation in dollars (rather than percentages) is less (more negative) than flat betting for all six hands.
"Then you can admire the real gambler, who has neither eaten, slept, thought nor lived, he has so smarted under the scourge of his martingale, so suffered on the rack of his desire for a coup at trente-et-quarante" - Honore de Balzac, 1829
Venthus
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January 1st, 2015 at 12:58:12 AM permalink
Quote: Donuts

This isn't intuitive to most people, but winrate of hands for blackjack is relatively low at only 42% roughly. You will another 48% of hands and push the rest.
http://www.blackjackincolor.com/truecount5.htm



I was actually just wondering about that number. If it was included alongside the edge tidbit, I feel like it'd alleviate a lot of issues.

...Also, 10% push? Way higher than I've guessed blind. Makes that 10 to 1 on ties marginally more attractive.
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