Surrender Question

**aceside** · 05-17-2022, 03:28 AM

Originally Posted by Gronbog

No we don't. Initially I had said that we do, which was incorrect.

I just thought about this again and got some new ideas. When counting card in hit-17 6-deck games, I surrender hard 17 vs A when TC<=+2 but stand when TC>+3. When counting card in stand-17 6-deck games, I do not have an index for the hand of hard 17 vs A.

However, one more thing still bothers me. A few 2-deck hit-17 games offer the surrender option. So, what is the surrender index for the hand in this game? Thank you in advance!

**G Man** · 05-17-2022, 06:08 AM

Originally Posted by aceside

I just thought about this again and got some new ideas. When counting card in hit-17 6-deck games, I surrender hard 17 vs A when TC<=+2 but stand when TC>+3. When counting card in stand-17 6-deck games, I do not have an index for the hand of hard 17 vs A.

However, one more thing still bothers me. A few 2-deck hit-17 games offer the surrender option. So, what is the surrender index for the hand in this game? Thank you in advance!

Some precision here:
In H17 games, you should Surrender 17 vs A when TC<+2 and Stand when TC =>+2

In S17 games, you should Surrender 17 vs A when TC<-4 and Stand when TC=>-4

For the DD H17 LS games, you Surrender 17 vs A when TC<+1 and Stand when TC=>+1

Note: For all these decisions, there's a point (very low TC) where you will start Hitting instead of Surrendering.

In S17 shoes: if TC <= -10
In H17 shoes: Can't tell but a lot less than -10
In DD H17 games: if TC <= -16

**aceside** · 05-17-2022, 10:36 AM

Originally Posted by G Man

In S17 games, you should Surrender 17 vs A when TC<-4 and Stand when TC=>-4

16

I didn’t know this part. I always stood on this hand in this situation. Nice of you!

**Cacarulo** · 05-17-2022, 10:45 AM

Originally Posted by G Man

Some precision here:
In H17 games, you should Surrender 17 vs A when TC<+2 and Stand when TC =>+2

In S17 games, you should Surrender 17 vs A when TC<-4 and Stand when TC=>-4

For the DD H17 LS games, you Surrender 17 vs A when TC<+1 and Stand when TC=>+1

Note: For all these decisions, there's a point (very low TC) where you will start Hitting instead of Surrendering.

In S17 shoes: if TC <= -10
In H17 shoes: Can't tell but a lot less than -10
In DD H17 games: if TC <= -16

I agree.

Sincerely,
Cac

**k_c** · 05-17-2022, 05:34 PM

This is detailed data for a hand of T-7 vs. ace, 2 decks, h17, late surrender using combinatorial analysis using HiLo. It includes number of cards remaining before up card is dealt, running counts to surrender/not surrender, and a calculated reference to true count at the surrender points. It would be a bit more accurate to use number of cards remaining after up card is dealt. However my CA computes before up card so I can compute all up cards at once.

Basically it shows for the most part to late surrender at a running count of <0 for most of the shoe and <-1 toward the end of shoe.

Referencing true count, it shows to late surrender for an approximate range of TC >=-15 to <0 for the largest portion of the shoe.

It also shows to late surrender for some extremely positive counts which are unlikely to be encountered.

Code:

T-7 v ace, 2 decks, h17, late surrender

Cards
(before
up card)  RC                     TC ref

102-100   r                      ----
99        <0, >=1                <0, >=.53
98        <1, >=2                <.54, >=1.07
97        <2                     <1.08
96-84     <1                     <.55 to <.63
83        <0                     <0
81        <0, >=19               <0, >=12.35
80        <0, >=20               <0, >=13.16
79        <0, >=21               <0, >=14.
78-77     <0, >=22               <0, >=14.86 to 15.05
76        <0, >=23               <0, >=15.95
75-74     <0, >=24               <0, >=16.86 to 17.10
73        <-30, >=-23, <0, >=25  <-21.67, >=-16.61 to <0, >=18.06
72        >=-22, <0, >=25        >=-16.11 to <0, >=18.31
71        >=-21, <0, >=26        >=-15.60 to <0, >=19.31
70        >=-21, <0, >=27        >=-15.83 to <0, >=20.35
69        >=-20, <0, >=27        >=-15.29 to <0, >=20.65
68        >=-20, <0, >=28        >=-15.52 to <0, >=21.73
67-66     >=-19, <0, >=28        (>=-14.97, >=-15.20) to <0, (>=22.06, >=22.40)
65-64     >=-18, <0, >=29        (>=-14.63, >=-14.86) to <0, (>=23.56, >=23.94)
63        >=-18, <0, >=30        >=15.10 to <0, >=25.16
62-61     >=-17, <0, >=30        (>=-14.49, >=-14.73) to <0, (>=25.57, >=26.)
60        >=-17, <0, >=31        >=-14.98 to <0, >=27.32
59-58     >=-16, <0, >=31        (>=-14.34, >=-14.60) to <0, (>=27.79, >=28.28)
57        >=-16, <0, >=32        >=-14.86 to <0, >=29.72
56        >=-15, <0, >=32        >=-14,18 to <0, >=30.25
55-53     >=-15, <0, >=33        (>=-14.44, >=-14.72, >=-15.)
                                      to <0, (>=31.78, >=32.28, >=33.)
52        >=-14, <0, >=34        >=14.27 to <0, >=34,67
51-50     >=-14, <0, >=35        (>=-14.56, >=-14.86) to <0, (>=36.40, >=37.14)
49        >=-13, <0, >=38        >=-14.08 to <0, >=41.17
48-46     >=-13, <0              (>=-14.38, >=-14.70, >=-15.02) to <0
45-42     >=-12, <0              (>=-14.18, >=-14.51, >=-14.86, >=-15.22) to <0
41-38     >=-11, <0              (>=-14.30, >=-14.67, >=-15.05, >=-15.46) to <0
37-36     >=-10, <0              (>=-14.44, >=-14.86) to <0
35-34     >=-10, <-1             (>=-15.29, >=-15.76) to (<-1.53, <-1.58)
33-30     >=-9, <-1              (>=-14.63, >=-15.10, >=-15.60, >=-16.14)
                                      to (<-1.63, <-1.68, <-1.73, <-1.79)
29-26     >=-8, <-1              (>=-14.85, >=-15.41, >=-16., >=-16.64)
                                      to (<-1.86, <-1.93, <-2., <-2.08)
25-22     >=-7, <-1              (>=-15.17, >=-15.83, >=-16.55, >=-17.33)
                                      to (<-2.17, <-2.26, <-2.36, <-2.48)
21-17     >=-6, <-1              (>=-15.60, >=-16.42, >=-17.33, >=-18.35, >=-19.5)
                                      to (<-2.6, <-2.74, <-2.89, <-3.06, <-3.25)
16-12     >=-5, <-1              (>=-17.33, >=-18.57, >=-20., >=-21.67, >=-23.64)
                                      to (<-3.47, <-3.71, <-4., <-4.33, <-4.73)
11-9      >=-4, <0               (>=-20.80, >=-23.11, >=-26.) to <0
8-7       >=-4, <1               (>=-29.71, >=-34.67) to (<7.43, <8.67)

k_c

**aceside** · 05-18-2022, 06:47 AM

Originally Posted by k_c

This is detailed data for a hand of T-7 vs. ace, 2 decks, h17, late surrender using combinatorial analysis using HiLo. It includes number of cards remaining before up card is dealt, running counts to surrender/not surrender, and a calculated reference

k_c

Wonderful work! I will use RC for this hand decision based on your results, but I found a tiny typo in this part of your code. Shouldn’t the TC be >=-14.27 to <0 ? Can you confirm? See below

“52 >=-14, <0, >=34 >=14.27 to <0, >=34,67”

It seems to me a minus sign is missing in front of the number 14.27.

**k_c** · 05-18-2022, 05:01 PM

Originally Posted by aceside

Wonderful work! I will use RC for this hand decision based on your results, but I found a tiny typo in this part of your code. Shouldn’t the TC be >=-14.27 to <0 ? Can you confirm? See below

“52 >=-14, <0, >=34 >=14.27 to <0, >=34,67”

It seems to me a minus sign is missing in front of the number 14.27.

Yes, there should be a minus sign. Input is 52 cards remaining before up card is dealt and input hand is T-7. After up card 51 cards remain and LS RC index turned out to be -14 for up card of ace and hand of T-7. TC = -14*52/51 = -14.27. In general TC = 52*RC/(cards remaining).

k_c

**aceside** · 05-19-2022, 08:25 AM

Originally Posted by k_c

Yes, there should be a minus sign. Input is 52 cards remaining before up card is dealt and input hand is T-7. After up card 51 cards remain and LS RC index turned out to be -14 for up card of ace and hand of T-7. TC = -14*52/51 = -14.27. In general TC = 52*RC/(cards remaining).

k_c

As a counter, we must take into consideration of the dealer’s upcard. This is especially important for DD games. Most professionals here recommend a deviation index of TC=+1 for surrendering the hand 17 vs A; however, you seem to suggest a slightly different index of TC=+0. At the 52-card penetration, if we count the dealer’s upcard A as -1, this will bring your index to even lower TC=-1. Is my understanding correct?

In practice, I’ll still use RC for this hand decision, and for this hand, I’ll use half the power as insurance needs.

**k_c** · 05-19-2022, 06:33 PM

Originally Posted by aceside

As a counter, we must take into consideration of the dealer’s upcard. This is especially important for DD games. Most professionals here recommend a deviation index of TC=+1 for surrendering the hand 17 vs A; however, you seem to suggest a slightly different index of TC=+0. At the 52-card penetration, if we count the dealer’s upcard A as -1, this will bring your index to even lower TC=-1. Is my understanding correct?

In practice, I’ll still use RC for this hand decision, and for this hand, I’ll use half the power as insurance needs.

I do take dealer's up card into consideration.

1. Hand composition is input. (Dealer up card is not considered yet.)
2. Running count is input.
3. Number of cards remaining is input. (Dealer up card is still not considered yet.)
4. A shoe comp is determined based on running count and cards remaining. (Dealer up card is still not considered yet.)
5. Hand expected values are computed for each up card for this shoe comp. (Dealer up card is now considered in the final count and one fewer cards remain.)
6. To generate an index, the range of all possible running counts is considered.

Below shows a calculation for a hand of T-7 with 52 cards remaining before up card is dealt. Running count is -13 before up card is dealt. Running count after up card is dealt depends on its tag. After an up card of ace is dealt running count is -14 and there are 51 cards remaining. Input rules are dealer hits soft 17, NDAS, LS allowed versus A and T, surrender allowed versus 2-9.

Code:

Number of decks: 2   Count tags {1,-1,-1,-1,-1,-1,0,0,0,1}
Player hand composition: 0, 0, 0, 0, 0, 0, 1, 0, 0, 1:  Hard 17, 2 cards
After player hand is dealt - Cards remaining: 52, Running count: -13
Subgroup removals: No subgroups are defined
Shoe comp (A-5):  {2.7996, 5.3296, 5.3296, 5.3296, 5.3296}
Shoe comp (6-10): {5.3296, 3.5621, 4.071, 4.071, 10.848}
After up card is dealt - Cards remaining: 51
Running count (up card 1 to 10): {-14,-12,-12,-12,-12,-12,-13,-13,-13,-14}

Up card   Stand      Hit   Double  Split 1  Split 2  Split 3  Surr     Strat

   1    -69.317  -60.990 -100.709                             -60.636   surr
   2    -25.820  -46.127  -92.254                             -50.000  stand
   3    -23.789  -46.206  -92.412                             -50.000  stand
   4    -20.952  -46.625  -93.249                             -50.000  stand
   5    -19.302  -42.725  -85.450                             -50.000  stand
   6    -16.801  -42.999  -85.997                             -50.000  stand
   7    -18.315  -39.144  -78.289                             -50.000  stand
   8    -35.871  -39.634  -79.267                             -50.000  stand
   9    -37.807  -42.983  -85.966                             -50.000  stand
  10    -41.497  -48.363  -91.237                             -52.745  stand

Overall hand EV vs all upcards: -29.8768

Press c or C for EV conditioned on no dealer blackjack, any other key to exit

To get total dependent indexes the hand composition is not considered, only the up card versus an input total. Total dependent index comes out to RC<1 for 52 cards remaining before up card (LS 17 vs ace).

That describes my methodology about as simply as I can. It allows for computing all up cards at once.

k_c

**Cacarulo** · 05-19-2022, 07:42 PM

Originally Posted by k_c

I do take dealer's up card into consideration.

1. Hand composition is input. (Dealer up card is not considered yet.)
2. Running count is input.
3. Number of cards remaining is input. (Dealer up card is still not considered yet.)
4. A shoe comp is determined based on running count and cards remaining. (Dealer up card is still not considered yet.)
5. Hand expected values are computed for each up card for this shoe comp. (Dealer up card is now considered in the final count and one fewer cards remain.)
6. To generate an index, the range of all possible running counts is considered.

Below shows a calculation for a hand of T-7 with 52 cards remaining before up card is dealt. Running count is -13 before up card is dealt. Running count after up card is dealt depends on its tag. After an up card of ace is dealt running count is -14 and there are 51 cards remaining. Input rules are dealer hits soft 17, NDAS, LS allowed versus A and T, surrender allowed versus 2-9.

Code:

Number of decks: 2   Count tags {1,-1,-1,-1,-1,-1,0,0,0,1}
Player hand composition: 0, 0, 0, 0, 0, 0, 1, 0, 0, 1:  Hard 17, 2 cards
After player hand is dealt - Cards remaining: 52, Running count: -13
Subgroup removals: No subgroups are defined
Shoe comp (A-5):  {2.7996, 5.3296, 5.3296, 5.3296, 5.3296}
Shoe comp (6-10): {5.3296, 3.5621, 4.071, 4.071, 10.848}
After up card is dealt - Cards remaining: 51
Running count (up card 1 to 10): {-14,-12,-12,-12,-12,-12,-13,-13,-13,-14}

Up card   Stand      Hit   Double  Split 1  Split 2  Split 3  Surr     Strat

   1    -69.317  -60.990 -100.709                             -60.636   surr
   2    -25.820  -46.127  -92.254                             -50.000  stand
   3    -23.789  -46.206  -92.412                             -50.000  stand
   4    -20.952  -46.625  -93.249                             -50.000  stand
   5    -19.302  -42.725  -85.450                             -50.000  stand
   6    -16.801  -42.999  -85.997                             -50.000  stand
   7    -18.315  -39.144  -78.289                             -50.000  stand
   8    -35.871  -39.634  -79.267                             -50.000  stand
   9    -37.807  -42.983  -85.966                             -50.000  stand
  10    -41.497  -48.363  -91.237                             -52.745  stand

Overall hand EV vs all upcards: -29.8768

Press c or C for EV conditioned on no dealer blackjack, any other key to exit

To get total dependent indexes the hand composition is not considered, only the up card versus an input total. Total dependent index comes out to RC<1 for 52 cards remaining before up card (LS 17 vs ace).

That describes my methodology about as simply as I can. It allows for computing all up cards at once.

k_c

There are two surrenders on your table that look weird:

-60.636
-52.745

Sincerely,
Cac

**k_c** · 05-19-2022, 08:06 PM

Originally Posted by Cacarulo

There are two surrenders on your table that look weird:

-60.636
-52.745

Sincerely,
Cac

Those are unconditional EVs. If I press 'c' to display EV conditioned on no dealer BJ:

Code:

Number of decks: 2   Count tags {1,-1,-1,-1,-1,-1,0,0,0,1}
Player hand composition: 0, 0, 0, 0, 0, 0, 1, 0, 0, 1:  Hard 17, 2 cards
After player hand is dealt - Cards remaining: 52, Running count: -13
Subgroup removals: No subgroups are defined
Shoe comp (A-5):  {2.800, 5.330, 5.330, 5.330, 5.330}
Shoe comp (6-10): {5.330, 3.562, 4.071, 4.071, 10.848}
After up card is dealt - Cards remaining: 51
Running count (up card 1 to 10): {-14,-12,-12,-12,-12,-12,-13,-13,-13,-14}

Up card   Stand      Hit   Double  Split 1  Split 2  Split 3  Surr     Strat

   1    -61.027  -50.450 -100.901                             -50.000   surr
   2    -25.820  -46.127  -92.254                             -50.000  stand
   3    -23.789  -46.206  -92.412                             -50.000  stand
   4    -20.952  -46.625  -93.249                             -50.000  stand
   5    -19.302  -42.725  -85.450                             -50.000  stand
   6    -16.801  -42.999  -85.997                             -50.000  stand
   7    -18.315  -39.144  -78.289                             -50.000  stand
   8    -35.871  -39.634  -79.267                             -50.000  stand
   9    -37.807  -42.983  -85.966                             -50.000  stand
  10    -38.099  -45.364  -90.728                             -50.000  stand

Overall hand EV vs all upcards: -29.8768

Press u or U to display unconditional EV, any other key to exit

Now if I press 'u' EVs revert to previous display.
Strategies can be obtained from either option.

k_c

**Cacarulo** · 05-19-2022, 08:22 PM

Ok.

Cac

**Gronbog** · 05-18-2022, 07:41 AM

Originally Posted by aceside

However, one more thing still bothers me. A few 2-deck hit-17 games offer the surrender option. So, what is the surrender index for the hand in this game? Thank you in advance!

Just a reminder that we are talking about the situation where you can only surrender or stand.

For a DD H17 game: