Penalty for violating BS

Mr. T

Well-Known Member
#1
Let me say of the bat, I am no Maths Wizard. Got distinction for Maths in High School but since I don't understand 90% of what is said here I know I am not in the same league as you guys. I have a question which I know you very smart guys can help me with.

For the BS player the House Advantage is about 0.50%. What would be the HA be increased for the general BJ player playing as some example the following.

1 not hiiting 16 vs 7
2 not hitting soft 18 vs 10
3 not doubling soft 18 vs 6
4 taking even moneyfor BJ against the dealers Ace

Then for the not so good BJ players

5 not doubling 11 vs 6
6 not splitting 8's vs 6
7 not doubling A6 vs 6

Then for some dasterdly players

8 doubling 16 vs 10
9 splitting 8's vs Ace, ( ENHC rules,no hole card )
10 hitting 17 vs 6

My guess is the HA is over 10% on this play alone. Could you tell me what is the actual number. Thanks
 

Sonny

Well-Known Member
#2
I think this post deserves its own thread so I'll liberate it from the other thread.

I don't have my copy of BJA handy, but I doubt the HA is near 10%. You have to be incredibly bad to get it that high. Even if you never split or double I think it is much lower than that. I'll have to check the book later, unless someone else has the numbers handy. The numbers for doubling and splitting can be found on bjmath (Archive copy) but the hitting numbers need to include multi-card hands.

-Sonny-
 

Mr. T

Well-Known Member
#3
Where I play just about everbody takes even money for BJ when the dealer has the Ace. That is a 3.5% HA already according to the Wizard. And you can't see this 3.5% difference in actual play.

You can see and know it is a bad play when the player do not split the pair of 8's vs 6. But what is the actual HA for this. That is what perhaps some very smart guy here can tell me



P.S. Sonny you are right to move this thread.
 

iCountNTrack

Well-Known Member
#4
1 not hitting 16 vs 7 (penalty is 6.79%)
2 not hitting soft 18 vs 10 (penalty is 3.69%)
3 not doubling soft 18 vs 6 (penalty is 8.91%)
4 taking even money for BJ against the dealers Ace (penalty is 50%)
5 not doubling 11 vs 6 (penalty is 32.14%)
6 not splitting 8's vs 6 (penalty is 48.53% if you chose to stand)
7 not doubling A6 vs 6 (penalty is 12.92% if you chose to hit instead)
8 doubling 16 vs 10 (penalty is 105.30% this is madness!)
9 splitting 8's vs Ace, ( ENHC rules,no hole card ) (penalty is 21.93% if you split instead of hitting)
10 hitting 17 vs 6 (penalty is 51.21%)


Now to get the overall ev of such blasphemous plays we just multiply each penalty by the corresponding hand frequency and sum everything.

6.79%*0.455+3.69%*0.367+8.91%*0.092+50%*4.79+32.14%*0.365+48.53%*0.044+12.92%*0.089+105.30*1.819+21.93%*0.044+51.23%*0.459


=4.76% ev penalty

keep in mind that was only for those plays and almost half of teh loss comes from taken even money.
 

Mr. T

Well-Known Member
#5
iCountNTrack you are Beautiful.

Now the 10 examples that I have given you is just a tiny sample of actual everyday play.

If we take all the combination of play there are 310 from the charts in this website. There are essentially 4 main options of play i.e. hit, stand, double and split. Only 1 is the right play.

Let us just assume that 50% of the all hands are mis played. Can you then extrapolate what the overall HA is. Make whatever assumptions you need as long as we know what these assumptions are.
 

iCountNTrack

Well-Known Member
#6
Mr. T said:
iCountNTrack you are Beautiful.

Now the 10 examples that I have given you is just a tiny sample of actual everyday play.

If we take all the combination of play there are 310 from the charts in this website. There are essentially 4 main options of play i.e. hit, stand, double and split. Only 1 is the right play.

Let us just assume that 50% of the all hands are mis played. Can you then extrapolate what the overall HA is. Make whatever assumptions you need as long as we know what these assumptions are.
Hmmm sorry that is a little too much to ask and i am swamped at the moment. I think my post was pretty informative on how to do what you are asking for.
 
#7
Mr. T said:
iCountNTrack you are Beautiful.

Now the 10 examples that I have given you is just a tiny sample of actual everyday play.

If we take all the combination of play there are 310 from the charts in this website. There are essentially 4 main options of play i.e. hit, stand, double and split. Only 1 is the right play.

Let us just assume that 50% of the all hands are mis played. Can you then extrapolate what the overall HA is. Make whatever assumptions you need as long as we know what these assumptions are.
There are multiple ways to misplay though, and calculating all those options would take forever but the following information might help you on what it is you're doing -

First, Appendix 1 of wizardofodds.com, I used this to find what i call "gray areas" in basic strategy, the spots where deviation doesn't hurt so bad and if you're feeling gamble-y, those gray areas would be the time to do it (instead of doubling a 12 or something equally crazy)
http://wizardofodds.com/blackjack/appendix1.html

Also, from Wizardofodds.com:
Never bust: For my analysis of this strategy I assumed the player would never hit a hard 12 or more. All other decisions were according to correct basic strategy. This "never bust" strategy results in a house edge of 3.91%.

Mimic the dealer: For my analysis of this strategy I assumed the player would always hit 16 or less and stand on 17 or more, including a soft 17. The player never doubled or split, since the dealer is not allowed to do so. This "mimic the dealer" strategy results in a house edge of 5.48%.

Assume a ten in the hole: For this strategy I first figured out the optimal basic strategy under this assumption. If the dealer had an ace up, then I reverted to proper basic strategy, because the dealer would have peeked for blackjack, making a 10 impossible. This "assume a ten" strategy results in a house edge of 10.03%.
 

KenSmith

Administrator
Staff member
#8
iCountNTrack said:
6.79%*0.455+3.69%*0.367+8.91%*0.092+50%*4.79+32.14%*0.365+48.53%*0.044+12.92%*0.089+105.30*1.819+21.93%*0.044+51.23%*0.459

=4.76% ev penalty

keep in mind that was only for those plays and almost half of teh loss comes from taken even money.
I almost didn't read this post, but then I saw you attributing more than half of a 4.76% cost to just taking even money!!

You seem to be figuring how much a game costs the player when blackjack pays 1:1 instead of 3:2.

A player who always takes even money when the dealer has an Ace costs this in a six deck game:

Frequency is 0.0035, about once every 283 hands.
The cost each time is 3.88% of the bet.
A player who always takes even money costs himself only 0.0035 * 3.88% = 0.01% EV.

I didn't examine any of the other numbers in your post to see if they appear accurate or not. I just knew that taking even money wasn't a big number.
 

iCountNTrack

Well-Known Member
#9
KenSmith said:
I almost didn't read this post, but then I saw you attributing more than half of a 4.76% cost to just taking even money!!

You seem to be figuring how much a game costs the player when blackjack pays 1:1 instead of 3:2.

A player who always takes even money when the dealer has an Ace costs this in a six deck game:

Frequency is 0.0035, about once every 283 hands.
The cost each time is 3.88% of the bet.
A player who always takes even money costs himself only 0.0035 * 3.88% = 0.01% EV.

I didn't examine any of the other numbers in your post to see if they appear accurate or not. I just knew that taking even money wasn't a big number.
Oops you are right Ken, i dont know why but i assumed in my head that taking even money against a dealer's ace i will use numbers that are independent of the dealer's upcard :). I triple checked all the other numbers and they are right.

Ok Here we go again

1 not hitting 16 vs 7 (penalty is 6.79%)
2 not hitting soft 18 vs 10 (penalty is 3.69%)
3 not doubling soft 18 vs 6 (penalty is 8.91%)
4 taking even money for BJ against the dealers Ace (penalty is 3.88%)
5 not doubling 11 vs 6 (penalty is 32.14%)
6 not splitting 8's vs 6 (penalty is 48.53% if you chose to stand)
7 not doubling A6 vs 6 (penalty is 12.92% if you chose to hit instead)
8 doubling 16 vs 10 (penalty is 105.30% this is madness!)
9 splitting 8's vs Ace, ( ENHC rules,no hole card ) (penalty is 21.93% if you split instead of hitting)
10 hitting 17 vs 6 (penalty is 51.21%)


Now to get the overall ev of such blasphemous plays we just multiply each penalty by the corresponding hand frequency and sum everything.

6.79%*0.455+3.69%*0.367+8.91%*0.092+3.88%*0.352+32.14 %*0.365+48.53%*0.044+12.92%*0.089+105.30*1.819+21. 93%*0.044+51.23%*0.459


=2.38% ev penalty

My apologies :)
 

Mr. T

Well-Known Member
#10
Scartch said:
There are multiple ways to misplay though, and calculating all those options would take forever but the following information might help you on what it is you're doing -

First, Appendix 1 of wizardofodds.com, I used this to find what i call "gray areas" in basic strategy, the spots where deviation doesn't hurt so bad and if you're feeling gamble-y, those gray areas would be the time to do it (instead of doubling a 12 or something equally crazy)
http://wizardofodds.com/blackjack/appendix1.html

Also, from Wizardofodds.com:
Never bust: For my analysis of this strategy I assumed the player would never hit a hard 12 or more. All other decisions were according to correct basic strategy. This "never bust" strategy results in a house edge of 3.91%.

Mimic the dealer: For my analysis of this strategy I assumed the player would always hit 16 or less and stand on 17 or more, including a soft 17. The player never doubled or split, since the dealer is not allowed to do so. This "mimic the dealer" strategy results in a house edge of 5.48%.

Assume a ten in the hole: For this strategy I first figured out the optimal basic strategy under this assumption. If the dealer had an ace up, then I reverted to proper basic strategy, because the dealer would have peeked for blackjack, making a 10 impossible. This "assume a ten" strategy results in a house edge of 10.03%.
Thanks. I will look more closely at what you said. This certainly sounds like a 10+% HA could be a reality.

Also from other imput here my sample of 10 plays out of a possible 155 misplay ( half of 310) could push the HA above 10%.
 

Mr. T

Well-Known Member
#11
KenSmith said:
I almost didn't read this post, but then I saw you attributing more than half of a 4.76% cost to just taking even money!!

You seem to be figuring how much a game costs the player when blackjack pays 1:1 instead of 3:2.

A player who always takes even money when the dealer has an Ace costs this in a six deck game:

Frequency is 0.0035, about once every 283 hands.
The cost each time is 3.88% of the bet.
A player who always takes even money costs himself only 0.0035 * 3.88% = 0.01% EV.

I didn't examine any of the other numbers in your post to see if they appear accurate or not. I just knew that taking even money wasn't a big number.

Ken, I just don't understand. the Wizard says Resplitting Ace has a -0.08% HA.
From experience this play occur so rarely yet there is a significant difference in the HA already.

Now we see Even Money play for BJ so often and yet you say it is only a 0.01% HA.
 

KenSmith

Administrator
Staff member
#12
Mr. T said:
Ken, I just don't understand. the Wizard says Resplitting Ace has a -0.08% HA.
From experience this play occur so rarely yet there is a significant difference in the HA already.
Resplitting Aces has a bigger impact because when it does come up, the cost is very high. Standing with (A,A) instead of being able to play two hands starting with an Ace on each is expensive. Even though the frequency is low, the cost is high, and the product of those two is therefore significant.
 

Mr. T

Well-Known Member
#13
KenSmith said:
Resplitting Aces has a bigger impact because when it does come up, the cost is very high. Standing with (A,A) instead of being able to play two hands starting with an Ace on each is expensive. Even though the frequency is low, the cost is high, and the product of those two is therefore significant.
I am talking about Respliting Ace. Spliting Ace is -0.19%.

Taking the arguement 1 step down the line. For H17, the HA is 0.22%. Using your arguement and assuming this occur 1 in 283 for the sake of arguement, then your EV is only 0.8%.

Are we talking House Advantage or something else.
 

Mr. T

Well-Known Member
#14
Mr. T said:
I am talking about Respliting Ace. Spliting Ace is -0.19%.

Taking the arguement 1 step down the line. For H17, the HA is 0.22%. Using your arguement and assuming this occur 1 in 283 for the sake of arguement, then your EV is only 0.8%.

Are we talking House Advantage or something else.
Sorry wrong calculation . This should read as your EV is only 0.008%.
 
#15
Mr. T said:
Also from other imput here my sample of 10 plays out of a possible 155 misplay ( half of 310) could push the HA above 10%.
Again, it depends on how you misplay. If half the time you're Doubling 20, that's going to be a huge disadvantage and knock HA well over 10. Splitting 20 is a moderate disadvantage. The chart will help you compare it all, then just multiply those odds by the percentage those situations come up and the frequency the player deviates.

Still hard to get blackjack's HA as bad as the lottery..
 
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