DorothyGale
DorothyGale
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October 8th, 2010 at 3:04:43 PM permalink
POST DELETED BY REQUEST

Dorothy
"Who would have thought a good little girl like you could destroy my beautiful wickedness!"
mkl654321
mkl654321
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October 8th, 2010 at 3:17:52 PM permalink
Even accepting the premise that a preponderance of 7s in the deck makes a dealer 17 more likely, you would also have to have a condition where 19s and 20s have not become more likely as well. And the likelihood of a dealer hard 17 would have to be increased enough to confer an edge that beats the inherent -EV of the side bet.

I would expect a preponderance of 7s to turn 60% of dealer stiffs (12, 13, 14) into 18-killers. After all, in many modified hi-lo counts, a 7 is counted as +0.5, meaning that two 7s out of the deck is equivalent to two, say, 4s out of the deck. It follows that a deck with a preponderance of 7s is mildly unfavorable to the player. That alone might be enough to negate any side bet advantage, because you have to make a plain ol' blackjack bet in order to make the side bet.
The fact that a believer is happier than a skeptic is no more to the point than the fact that a drunken man is happier than a sober one. The happiness of credulity is a cheap and dangerous quality.---George Bernard Shaw
ChesterDog
ChesterDog
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October 8th, 2010 at 4:34:53 PM permalink
Quote: mkl654321

...a deck with a preponderance of 7s is mildly unfavorable to the player. That alone might be enough to negate any side bet advantage, because you have to make a plain ol' blackjack bet in order to make the side bet.



A shortage of aces, as well as a preponderance of 7's, is good for the sidebet. So, the main blackjack bet would tend to be really bad when the sidebet is at positive EV. Counters who "play all" could have a side count of aces vs 7's to play Instant 18 as a side bet, but counters who "wong out" at negative counts might do better overall.
DorothyGale
DorothyGale
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October 8th, 2010 at 7:09:05 PM permalink
POST DELETED BY REQUEST

Dorothy
"Who would have thought a good little girl like you could destroy my beautiful wickedness!"
mkl654321
mkl654321
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October 9th, 2010 at 12:28:22 AM permalink
The piece of data that is missing is the house edge on the "normal" hand with these various counts. If the normal hand is sufficiently -EV to negate the side bet 18 hand's +EV, then the count wouldn't help.

I also doubt very much that the 7s and the As have equal weight, which would lead to gross inaccuracies if that was the case.

You may be on to something, but I doubt that a simple Ace-7 count alone would do the job here.
The fact that a believer is happier than a skeptic is no more to the point than the fact that a drunken man is happier than a sober one. The happiness of credulity is a cheap and dangerous quality.---George Bernard Shaw
Wizard
Administrator
Wizard
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October 9th, 2010 at 12:18:44 PM permalink
I'm sorry to see Dorothy deleted her posts, which were outstanding. I remember the gist of the tables, and if I have time will try to recreate them myself. However, I would appreciate a comment on why Dorothy deleted them.
It's not whether you win or lose; it's whether or not you had a good bet.
DorothyGale
DorothyGale
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October 9th, 2010 at 2:11:20 PM permalink
The following analysis is for blackjack dealt from 6 decks, H17, dealt to 240 cards. I simulated 25 million shoes dealt to this depth, using a count system of A = +1 and 7 = -1, all other cards were 0. This is a balanced count (obviously), so I applied true count conversions by rounding (not truncating or flooring ... rounding ... ok?). This analysis demonstrated that for a true count of 2 or higher the player has the edge over this bet. I also determined the frequency of the various counts. In doing this analysis, I didn't assume any fixed number of players. Rather I dealt 2 to 7 cards at random to the "players" to simulate their depletion of the shoe.

So, here it is again ... many thanks to you, Mr. Wizard, you're the best ...

True Count Edge Frequency
-8 -10.35% 0.03%
-7 -9.47% 0.07%
-6 -8.67% 0.17%
-5 -7.78% 0.36%
-4 -7.03% 0.73%
-3 -6.04% 1.49%
-2 -5.11% 3.11%
-1 -4.10% 7.02%
0 -2.37% 55.67%
1 -1.01% 18.38%
2 0.09% 7.00%
3 1.10% 3.10%
4 1.97% 1.49%
5 2.84% 0.73%
6 3.60% 0.36%
7 4.60% 0.17%
8 5.12% 0.07%


Overall, if you played this bet every time the true count was 2 or more, then you would play it on 12.96% of the hands and have an average edge of 0.91% over the house. I would rank this side bet as beatable, but not worth it. There may be a stronger count available, what do I know?

Ms. D.
"Who would have thought a good little girl like you could destroy my beautiful wickedness!"
MathExtremist
MathExtremist
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October 9th, 2010 at 9:59:36 PM permalink
Interesting. Given the re-post, can you shed some light on who requested the deletion of your first two posts?
"In my own case, when it seemed to me after a long illness that death was close at hand, I found no little solace in playing constantly at dice." -- Girolamo Cardano, 1563
DorothyGale
DorothyGale
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October 10th, 2010 at 7:20:37 AM permalink
Quote: MathExtremist

Interesting. Given the re-post, can you shed some light on who requested the deletion of your first two posts?


Glad you found it interesting ... the bet is not especially beatable ... if the max wager is $100 then on 12 hands per 100 you'll make about 91 cents, for a win rate of $10.92 per 100 hands. Not exactly time to retire and play this bet, is it? If the bet had any real issues, the deletions would have stood up.

Ozzily yours,

Ms. D.
"Who would have thought a good little girl like you could destroy my beautiful wickedness!"
Instanto18
Instanto18
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November 18th, 2010 at 9:11:02 AM permalink
I feel as if this is for a stand soft 17, rather than hit. I see you say in your post it is H17, but I saw someone else ran this scenario, and this was the table for standing on all 17's.

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