House Edge Calculations

Good evening everyone!

I had a quick question - is house edge for blackjack calculated based on total-basic strategy, composition-based basic strategy, or something else entirely?

Recently I have been using the Wizard of Odds blackjack hand calculator which has been super useful in teaching myself some composition-based basic strategy. If anyone wants I can details some of my more "interesting" findings (note: interesting is subjective) for others to use. I was wondering if the code for this, or a similar program is available online? I want to adjust it for other games such as Zappit or Spanish 21, and while I can code this myself I don't want to reinvent the wheel if someone already has made something very similar.

I think Spanish 21 could have particularly lucrative compositional-based basic strategy, considering that you win with six cards which adds another element to consider that total-based basic strategy might not be able to sufficiently take advantage of. Let me know what you think.

In regular blackjack composition dependent basic strategy really only has use in a single deck game. 7,7 vs. 10 is stand in a SD game, that's a well known one. What it's really doing there is a rudimentary form of counting, knowing how valuable the 7 is when playing 14 vs. 10. I don't think you will find much else in comp-dependent strategy for blackjack.

Spanish 21 is a different story and just because of the bonus hands. It is significant in the game. But the most important of the special Spanish 21 rules is the automatic win on 21.

There’s also composition dependent strategy on 16 v 10 and 12 vs 2. But it’s all very marginal.

Splitting 7's vs 10 as a Stand in a 1-deck game is kinda just total-basic strategy not composition dependent...

There are many other situations for composition dependent strategy.

I do not care if it is all very marginal. I'm in this for the math, not to save 76¢ on average for every million dollars I gamble :D

Quote: harris

Good evening everyone!

I had a quick question - is house edge for blackjack calculated based on total-basic strategy, composition-based basic strategy, or something else entirely?

Recently I have been using the Wizard of Odds blackjack hand calculator which has been super useful in teaching myself some composition-based basic strategy. If anyone wants I can details some of my more "interesting" findings (note: interesting is subjective) for others to use. I was wondering if the code for this, or a similar program is available online? I want to adjust it for other games such as Zappit or Spanish 21, and while I can code this myself I don't want to reinvent the wheel if someone already has made something very similar.

I think Spanish 21 could have particularly lucrative compositional-based basic strategy, considering that you win with six cards which adds another element to consider that total-based basic strategy might not be able to sufficiently take advantage of. Let me know what you think.
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harris,

Here is a useful post for you:

Quote: Mental

There is a really great open source BJ evaluator already available on github courtesy of Eric Farmer: https://github.com/possibly-wrong/blackjack

This has been tested by a number of experts and does finite deck calculations for a variety of rules. I found the code easy to understand and modify.
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I too have frequently used Eric's programs.

Dog Hand

12 v 4 is another one. 10+2, hit, otherwise stand.

Quote: harris

There are many other situations for composition dependent strategy.

I do not care if it is all very marginal. I'm in this for the math, not to save 76¢ on average for every million dollars I gamble :D
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We do not want “marginal” problems; we want “substantial” to say the least. However, your interest in Spanish 21 is well justified because you have demonstrated tremendous math skills. I’ve asked this question a couple of times here, but nobody hasn’t shown any interest. Here it is.

Consider a 6-deck S-17 Spanish 21 game. The multiple cards 21 bonus pay is:

A five-card 21 pays 3:2;
A six-card 21 pays 2:1;
A seven or more-cards 21 pays 3:1.

Wizard shows that the basic strategy for a three or more-cards 11 vs 10 is Hit if Double-down voids these bonus pays. What is the correct strategy if these bonuses are still paid even after Double-down?

I'm assuming based on your explanation: if you bet $100, got a five-card 11, and doubled it (to $200) and got 21, you would get paid 2:1 ($400).

Based on some quick calculations I can say that Doubling would be better at any card number 11 vs 10. This could have also been a logic problem instead of using calculations :D I hope I did not misunderstand your question.

Quote: harris

I'm assuming based on your explanation: if you bet $100, got a five-card 11, and doubled it (to $200) and got 21, you would get paid 2:1 ($400).

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This is correct. For four-card, five-card, and more-card hands, it’s clear the correct strategy is Double. However, for a three-card 11 v 10, it’s not so clear. Let me use this hand as an example:

For the hand 3,6,2 v 10, should I Hit or Double? If I Double, I will lose any possible bonus payouts in the future, because I cannot Hit anymore after a Double. If I Hit, I will lose the opportunity to Double. What’s your call?

Good catch - I misunderstood the rules of Spanish 21 and thought you could just hit normally after doubling. I have only played a few hands of this game in my life.

I'm just going to guess you should hit in this case based on vibes (someone else can calculate it) but it might depend on whether or not "double down rescue" is offered.

Double down rescue is always allowed in Spanish 21.