EV's after double down
June 2nd, 2020 at 12:15:54 PM
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Dear Wizard,
I have a question about your table from the following link: I am not allowed to put links in the thread so in the wizard of odds website paste this text after the basic link: games/blackjack/appendix/9/euro-6ds17r4/ (Six deck, dealer stands on soft 17, no hole card). When we look at the ev when you double a 4 and 3 against a dealer's ace, this is -1,399876. This value is lower than minus 1. If you bet 1 and you choose to double, it is indeed logical that you can lose up to 2 units. But there are also lots of situations in which your ev is exactly -1,000000. How is this possible? For example when the dealer has a 4 and you have a 10 and a 6. This means that in this situation, you will win exactly 25,00000% of the time you play this hand. But the same is true if you hold a 10 and 2 or 10 and 9.
Do I miss something important here?
Anyway, thanks a lot for the provided tables! They helped me out a lot! Keep up the good work!
Greetings from the Netherlands,
Casper
I have a question about your table from the following link: I am not allowed to put links in the thread so in the wizard of odds website paste this text after the basic link: games/blackjack/appendix/9/euro-6ds17r4/ (Six deck, dealer stands on soft 17, no hole card). When we look at the ev when you double a 4 and 3 against a dealer's ace, this is -1,399876. This value is lower than minus 1. If you bet 1 and you choose to double, it is indeed logical that you can lose up to 2 units. But there are also lots of situations in which your ev is exactly -1,000000. How is this possible? For example when the dealer has a 4 and you have a 10 and a 6. This means that in this situation, you will win exactly 25,00000% of the time you play this hand. But the same is true if you hold a 10 and 2 or 10 and 9.
Do I miss something important here?
Anyway, thanks a lot for the provided tables! They helped me out a lot! Keep up the good work!
Greetings from the Netherlands,
Casper
June 2nd, 2020 at 12:53:15 PM
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The -1's look wrong. Where the dealer can't get Blackjack you can see some correct figures at https://wizardofodds.com/games/blackjack/appendix/9/6dh17r4/
On your page
For instance if you hit 16 vs 7 your EV is quoted about -0.408432 or -0.408624, whereas the double is quoted as -1 (-0.817247 on 6dh17r4).
If you weren't going to hit any further under normal strategy, then double should be twice the Hit EV.
I've had a quick look and some of the other Euro ones are wrong, so there seems to be something gone wrong with the program to load up the figures.
21h BST Edit: Taking doubling 7 5 vs A, where the EV should be less than -1, shows the problem for all the No Peek scenarios. I've sent a PM to the wizard.
On your page
For instance if you hit 16 vs 7 your EV is quoted about -0.408432 or -0.408624, whereas the double is quoted as -1 (-0.817247 on 6dh17r4).
If you weren't going to hit any further under normal strategy, then double should be twice the Hit EV.
I've had a quick look and some of the other Euro ones are wrong, so there seems to be something gone wrong with the program to load up the figures.
21h BST Edit: Taking doubling 7 5 vs A, where the EV should be less than -1, shows the problem for all the No Peek scenarios. I've sent a PM to the wizard.
June 2nd, 2020 at 7:22:30 PM
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I'm out of town right now so can't look at my code that made this program. However, as I recall, going back about 15 years, to speed up the program I assigned an EV of -1 to obvious situations, as opposed to taking time to calculate it exactly.
When I get home, I'll probably footnote those "-1" situations with a letter to explain that the EV was not implicitly calculated for the reason I just stated.
Mike
When I get home, I'll probably footnote those "-1" situations with a letter to explain that the EV was not implicitly calculated for the reason I just stated.
Mike
"For with much wisdom comes much sorrow." -- Ecclesiastes 1:18 (NIV)
June 3rd, 2020 at 12:06:21 AM
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Thanks a lot for the quick replies.
Enjoy your vacation!
Greetings,
Casper
Enjoy your vacation!
Greetings,
Casper
