Modified martingale

[aslan]

I am fairly new to blackjack, but not to gambling. I have a friend who insists that he always wins by playing a combination of perfect basic strategy and a modified martingale progression. If he loses one unit he then bets two units, and if he loses the two units, he then bets four units. If he loses the four unit bet, he returns to one unit. If he wins, he always returns to betting one unit. He claims it overcomes the houses .44% advantage. He also says that one must be willing to risk at least 60 units for his system to work.

I told him I didn't think his betting system could have any effect on the odds, just increase the speed with which he would either win or lose using basic strategy, and will eventually cost him big time. But I can't seem to explain why to his satisfaction. Can anyone come up with an explanation that is easy to understand so I can persuade my friend to drop this strategy?

[Kasi]

Originally Posted by aslan

I am fairly new to blackjack.... Can anyone come up with an explanation that is easy to understand so I can persuade my friend to drop this strategy?

You can lead a horse to water but you can't make him drink

But, in a way, he's half-right without knowing it because he will be able to come out ahead a high percentage of the time. That's the nice thing about this game. Since you're expected to lose so little in the first place, it just doesn't take too much to come out ahead in a given session. Doesn't the Martingale win your unit over 80% of the time?

Put another way, that 0.44% means that at a full table, you are only supposed to lose 1 unit every 2.5 hours or so.

I won $100/day, as an experiment to myself, on the internet for 43 straight days with a $6/unit. So, obviously, I needed to net 16.66 units to achieve my goal. Increasing bets when behind and stpping when I made my $100. Some days I won it 1n 15 minutes, some days it took a couple hours. On the 44th day I was up $99 and next thing I know I'm down about $1500 chasing that one lousy dollar. So I stopped and my streak was broken. But I won 97.7% of my sessions. And even made some money. Did I overcome the house edge? - well you already know the answer to that.

So my advice to you is don't worry what your friend does and if, while you're playing, you feel lucky from time to time, go ahead and bet it!

[ihate17]

How does that martingale overcome a losing streak. In approx every 20 hours of blackjack play you should have a losing streak of at least 10 in a row. On a personal basis, I can document 4 streaks of losing over 20 in a row, with the latest and biggest being somewhere between 25-27 hands lost and an additional 2 pushes.
Now since he will never lose more than 4 in a row before going back to a one unit bet, if he catches a streak like the above he will not need to bet millions upon millions to win one unit, but one streak will wipe out perhaps 100 small winning sessions is the matter of 15 minutes, resulting in his eventually being behind by whatever percentage his errors add to the house edge.

ihate17

[aslan]

Originally Posted by ihate17

How does that martingale overcome a losing streak. In approx every 20 hours of blackjack play you should have a losing streak of at least 10 in a row. On a personal basis, I can document 4 streaks of losing over 20 in a row, with the latest and biggest being somewhere between 25-27 hands lost and an additional 2 pushes.
Now since he will never lose more than 4 in a row before going back to a one unit bet, if he catches a streak like the above he will not need to bet millions upon millions to win one unit, but one streak will wipe out perhaps 100 small winning sessions is the matter of 15 minutes, resulting in his eventually being behind by whatever percentage his errors add to the house edge.

ihate17

Thanks! I was looking for numbers to back up what I felt instinctively about his method. So, if a ten streak loser appears he will lose 1+2+4 units three times, or 21 units and gain back only one unit on the tenth loss in the streak. And what about all the 9, 8, 7, 6, 5, 4 losing steaks during that 20 hours! I think he's exposing himself to a lot of serious downside.

[positiveEV]

It's not hard. Every hand you play, you loose on average the house edge. If you are not counting, you can consider every hand is independent of each other (it's not really the case but you won't know your advantage without counting. So, if you loose the house edge on every bet, no matter when you make big bets or small bets you will always loose the same amount of time.

Example: if you have 49% chance to win and 51% chance to loose, no matter how much you bet you will always loose an average of 2% of your bet, and even if you try a system that vary your bets you will loose at the same rate on every separate hand. If you bet 1 unit 100x, you will loose 2x1 unit. If you bet 2 units 50x, you will loose 1x2 units. If your system make you bet 100 units only once in a while, you will still loose in the long run (and in the short run you will either win or loose a lot).

Don't know if it's clear, but no matter how you change your bet, if you play a game with an edge and you don't know how to mathematically overcome the edge, you will loose.

[ScottH]

Originally Posted by asiafever

It's not hard. Every hand you play, you loose on average the house edge. If you are not counting, you can consider every hand is independent of each other (it's not really the case but you won't know your advantage without counting. So, if you loose the house edge on every bet, no matter when you make big bets or small bets you will always loose the same amount of time.

Example: if you have 49% chance to win and 51% chance to loose, no matter how much you bet you will always loose an average of 2% of your bet, and even if you try a system that vary your bets you will loose at the same rate on every separate hand. If you bet 1 unit 100x, you will loose 2x1 unit. If you bet 2 units 50x, you will loose 1x2 units. If your system make you bet 100 units only once in a while, you will still loose in the long run (and in the short run you will either win or loose a lot).

Don't know if it's clear, but no matter how you change your bet, if you play a game with an edge and you don't know how to mathematically overcome the edge, you will loose.

Having a 49% chance of winning doesnt mean you are at a 2% disadvantage. There are other things that reduce that edge such as 3:2 on naturals. I think the actual win % in blackjack is like 47%, but the edge is only around a half of a percent for most games. So you expect to lose about 0.5% of what you wager each hand.

[positiveEV]

Originally Posted by ScottH

Having a 49% chance of winning doesnt mean you are at a 2% disadvantage. There are other things that reduce that edge such as 3:2 on naturals. I think the actual win % in blackjack is like 47%, but the edge is only around a half of a percent for most games. So you expect to lose about 0.5% of what you wager each hand.

My example was not for blackjack, I don't know the exact odds for BJ and you also have to include double downs, splits, etc. I just wanted to make a simple example.

[positiveEV]

Let's test this system on a game with exactly 50% chance to win and to loose, so no house edge.

50% if the time, you will win 1 unit.
25% of the time you will win 2 units and loose a total of one (the one you lost on the first bet).
12.5% of the time you will win 4 units and loose a total of one 3.
6.25% of the time you will win 1 unit and loose a total of one 7.
3.125% of the time you will win 2 units and loose a total of one 8.
1.5625% of the time you will win 4 units and loose a total of one 10.
0.78125% of the time you will win 1 units and loose a total of one 14.
I can go on and on but let's say you stop there as it don't change anything anyway. You will loose 15 units 0.78125% of the time.

50(1)+25(1)+12.5(1)+6.25(-6)+3.125(-6)+1.5625(-6)+0.78125(-13)+0.78125(-15)=0

So using your system on a break even game, you will not make any money. How can you expect to make any in a game with an edge?

[Mimosine]

can't we just outlaw any talk of progression on the general thread and insist that it all goes to the voodoo one?

i've only been on here a few months and am tired of seeing these questions/threads/posts over and over again.

[Kasi]

Originally Posted by Mimosine

can't we just outlaw any talk of progression on the general thread and insist that it all goes to the voodoo one?
i've only been on here a few months and am tired of seeing these questions/threads/posts over and over again.

It would be nice if we all could acknowledge that all betting systems are equally worthless. And avoid phrases like "it overcomes the houses .44% advantage".

But sometimes I think what gets lost in discussions like this is the high-percentage of the time one can come out ahead. I don't doubt at all that Aslan's friend has won 20 times in a row. That's nothing. And maybe it's even actually a pretty risky system compared to others.

I mean I've played ~200,000 hands on the internet, up 213 flat-betting units for a 100.10% payback as pure luck would have it. But, since my goal was almost always to finish a little ahead from where I started, my actual payback is 101.07% due to employing very mild, mostly negative, nothing even remotely close to a Martingdale, modified or otherwise, progressions from time to time.

So, I don't know, how lucky is making up 1% over that many hands with "bigger bets"?

It's so easy to prove mathematically how a betting system won't work but the fact is, while it won't work in the "long-run", the long run can be a very long time indeed.

My point is, in my case, at 60 hds/hr at a full table, that's playing 8 hours a day, 5 days a week, for over a year and a half. I imagine there are many recreational players that might not play that much in a lifetime in a B&M casino.

So, if someone wants to bet a Martingdale or increase a bet because the Sacred Flow (I luv that lol) is coming , let them - they just might win a little over a very long period of time. After all, betting in any manner whatsoever is just as valid as flat-betting every hand so, if u want to take a very little risk, go ahead and do it. You very well might not live long enough to experience the mathematical proof of the flaw in your "system".

OK - go ahead and massacre me now.