Griffin - EOR vs. Betting Effect

London Colin

Well-Known Member
#21
Spyros Acebos said:
Please explain where in the results screen I find the EOR for each results screen.

I appreciate your (or Don's or anyone else's) response. Just trying to understand where the CDCA online software spits out the EoR's.

Is it the decimal number in the black (poq
sitive number) or red (negative number) box immediately below: Player Expected Values (in %)?
That figure is the EV for the given deck composition. EORs are not displayed anywhere.

As Don said, you need to calculate the EOR by first computing the EV for the full deck, then repeating with one card removed, then subtracting the first result from the second.
 
#22
London Colin said:
That figure is the EV for the given deck composition. EORs are not displayed anywhere.

As Don said, you need to calculate the EOR by first computing the EV for the full deck, then repeating with one card removed, then subtracting the first result from the second.
LC, thank you.

I am lost. I was dividing the EV for a Full Deck by the EV for the sum of EV results (under columns 2-A) for a Two. Then I repeated this for a Three, and so one until Ace. But my EORs do not seem to make any sense.

So, am I supposed to take the sum of EVs for a Full Deck (bottom numbers in the columns 2-A) and then subtract the EVs for a Two, and lather, rinse, and repeat for a Three, etc. .... Ace? If so, I get the following data (cannot attach spreadsheet, so attaching PDF print from spreadsheet) that makes no sense.

Not sure how to take the data from the CDCA Compute Results and which specific data to identify the EV for a Full Deck, as well as the Two through Ace cards in order to calculate the EORs.

UPDATE: DOH! I was performing the subtraction in reverse. By subtracting in the proper order, the EV (from top left cell under Players' Expected Values (in %) for a Full Deck from the Players' Expected Value (in %) for each Card Rank, I generated a spreadsheet for Basic Strategy, 1D, H17, 3:2, NS, DAS, SA1, that looks like the attached PDF file (see attached PDF since unable to upload XLS files). The results are not far off from the data in Don's Table D17 in BJA3.

THANK YOU DON, LC and SageFrog!!!!!!
 

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London Colin

Well-Known Member
#23
The top-left figure in the results is the overall EV. This is the only figure you need.

Compute the EV for the full deck.
Compute the EV with a given card removed.
Subtract to give the EOR of the given card
 
#24
London Colin said:
The top-left figure in the results is the overall EV. This is the only figure you need.

Compute the EV for the full deck.
Compute the EV with a given card removed.
Subtract to give the EOR of the given card
Exactly what I eventually did, that resulted in the spreadsheet (printed to PDF file and attached to last post).

Would I follow the same steps to generate EORs for Spanish 21 (albeit 12 ten valued cards per deck, rather than 16)? If so, see attached PDF for chart of EVs and EORs for Spanish 21, assuming Basic Strategy, 1D, H17, NS, 3:2, DAS, SA1.
 

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London Colin

Well-Known Member
#25
Spyros Acebos said:
Exactly what I eventually did, that resulted in the spreadsheet (printed to PDF file and attached to last post).
No it isn't what you did.. The overall EV is the only figure you need. Ignore everything else on the screen.

You need to hit Compute eleven times, once for the full deck and once for each of the ten possible 51-card decks.

Spyros Acebos said:
Would I follow the same steps to generate EORs for Spanish 21 (albeit 12 ten valued cards per deck, rather than 16)? If so, see attached PDF for chart of EVs and EORs for Spanish 21, assuming Basic Strategy 1D, H17, NS, 3:2, DAS, SA1.
This software doesn't know anything about the rules of Spanish 21.
 
#26
London Colin said:
No it isn't what you did.. The overall EV is the only figure you need. Ignore everything else on the screen.

You need to hit Compute eleven times, once for the full deck and once for each of the ten possible 51-card decks.
That is exactly what I did for each card value, as well as the initial full deck EV.

Reset the deck to 52 cards in between each iteration, before removing 1 card.

Then view the top left red/black cell to locate the EV for each time the Compute button is hit.

Then subtract Full Deck EV from EV for each result for each card removed, before moving on to the next reset and compute iteration. Subtraction function generates the EOR for each card rank.

London Colin: Are you saying I am utilizing the wrong cell for Overall EV? If so, where is that cell on the results screen? Are you referring to the Insurance EV at the bottom of the screen?
 
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London Colin

Well-Known Member
#27
Spyros Acebos said:
That is exactly what I did for each card value, as well as the initial full deck EV.

Reset the deck to 52 cards in between each iteration, before removing 1 card.

Then view the top left red/black cell to locate the EV for each time the Compute button is hit.

Then subtract Full Deck EV from EV for each result for each card removed, before moving on to the next reset and compute iteration. Subtraction function generates the EOR for each card rank.
Ah, OK. It sounded like you were still being confused by the 2-A columns.
 
#28
London Colin said:
Ah, OK. It sounded like you were still being confused by the 2-A columns.
So, that's good to go?

As for Spanish 21, I take it you are saying that I can't just set the deck composition to 48 cards, with only 12 (not 16) ten rank cards. Correct?
 

London Colin

Well-Known Member
#29
Spyros Acebos said:
So, that's good to go?
I'm not too sure what you are asking. You've got the method for calculating EORs. So, yes, you can use that for any set of rules that interest you, if that's what you mean.

(Regarding the rules - In one of your very first attached images it looked like you missed a check box for surrender vs 2-9.)

Spyros Acebos said:
As for Spanish 21, I take it you are saying that I can't just set the deck composition to 48 cards, with only 12 (not 16) ten rank cards. Correct?
Of course you can't. I'm not really familiar with Sp21, but I know It's a different game, with numerous differences in the rules, compared to bj.
 

DSchles

Well-Known Member
#30
sagefr0g said:
thank you for your response.

three reasons, i was curious whether kc's tdca and cdca software would work for determining EOR s.
also, i did try the application suggested. i found myself confuse regarding the following settings:

1.
EV (unconditional when not checked)
Conditioned on no dealer BJ where applicable

2.
Compute mode
Best strat Basic strat

3.
Depleted shoe split strat (Re: basic strat)
Pre-split Optimal strat of 1st split hand

errhh, i believe you stipulated that #2 above should be set at Basic Strat ?
Use basic strategy for 2 and 3, and dealer has checked and doesn't have a natural for 1.

Don
 

DSchles

Well-Known Member
#31
Is everything clear now, or is there still a question on the table? In the shoe composition, you first leave all 52 cards and calculate the full-deck favorability (house edge). Then, you remove a single card of a given rank and recalculate the edge with 51 cards. Then you subtract the former from the latter, and you get the EOR of the latter.

Clear?

Don
 
#32
DSchles said:
Is everything clear now, or is there still a question on the table? In the shoe composition, you first leave all 52 cards and calculate the full-deck favorability (house edge). Then, you remove a single card of a given rank and recalculate the edge with 51 cards. Then you subtract the former from the latter, and you get the EOR of the latter.

Clear?

Don
Worked for me after tinkering with cdca a few times.

Don (or anyone else), do you know of any software out there that would let me work through generating EORs and EV for Spanish 21, in a similar fashion to the method used to do so for blackjack with cdca?
 

gronbog

Well-Known Member
#34
London Colin said:
Of course you can't. I'm not really familiar with Sp21, but I know It's a different game, with numerous differences in the rules, compared to bj.
Not to mention a very different basic strategy. In addition, Spanish 21 is patented as a 6 or 8 deck game. Single deck EORs are not useful because of this and because some Spanish 21 bonus hands are not even possible with fewer than 3 decks. For example, any bonus hand requiring suited 777.
 

sagefr0g

Well-Known Member
#35
Using the suggested online software (http://www.bjstrat.net/cgi-bin/cdca.cgi) my values for betting eor came close but not exactly the same as table D17

here are the values i came up with for line one of table D17 pg 522 fpr a S17 NDAS game, base rules: DOA, SPA1, SPL3 :

card removed:

2 eor = 0.3825

3 eor = 0.4362

4 eor = 0.5436

5 eor = 0.7023

6 eor = 0.4147

7 eor = 0.2842

8 eor = 0.0023

9 eor = -0.169

10 eor = -0.5030

A eor = -0.5953

edit: 4 eor above should read 4 eor = 0.5536 end edit
 
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#36
gronbog said:
Not to mention a very different basic strategy. In addition, Spanish 21 is patented as a 6 or 8 deck game. Single deck EORs are not useful because of this and because some Spanish 21 bonus hands are not even possible with fewer than 3 decks. For example, any bonus hand requiring suited 777.
Gronbog,

So are you suggesting that EORs can indeed be generated for 6D and 8D Spanish 21 games?

If so, other than perhaps your proprietary customized simulation engine, are there any CA packages out there (MGP, simmar, ICountNTrack, etc.; knowing now that kc's bjstrat CDCA application is not suitable) that I could use to generate EORs for Spanish 21 games?
 

gronbog

Well-Known Member
#37
I can do it using simulation, but it takes a long time. I know that simmar handles Spanish 21 via CA. Can't comment on the others.
 

DSchles

Well-Known Member
#38
sagefr0g said:
Using the suggested online software (http://www.bjstrat.net/cgi-bin/cdca.cgi) my values for betting eor came close but not exactly the same as table D17

here are the values i came up with for line one of table D17 pg 522 fpr a S17 NDAS game, base rules: DOA, SPA1, SPL3 :

card removed:

2 eor = 0.3825

3 eor = 0.4362

4 eor = 0.5436

5 eor = 0.7023

6 eor = 0.4147

7 eor = 0.2842

8 eor = 0.0023

9 eor = -0.169

10 eor = -0.5030

A eor = -0.5953

Yet again, I am sorry but these are not the right values. You HAVE to set "Basic Strategy" under Compute Mode. I checked a single value (the 4) and found it to be wrong.

Don
 
#39
Don, does the box for: "Depleted shoe split strat (Re: basic strat)" matter.

If so, what impact do the options have: "Pre-split" OR "Optimal strat of 1st split hand"? What should it be set for when generating EVs for 1D game to then use in determining EORs?

I used Pre-split, but figured that I may as well ask.
 

sagefr0g

Well-Known Member
#40
DSchles said:
Yet again, I am sorry but these are not the right values. You HAVE to set "Basic Strategy" under Compute Mode. I checked a single value (the 4) and found it to be wrong.

Don
good catch sir, either i did a typo on the four card or an arithmetic error. it should have been 0.5536 . close to the value for a four in table D17, but not exactly the same, whereas the table has 0.5582 (1st line of table D17)
by the way, the settings i used are depicted in the image below:

settingsused-jpg.9024
 
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