Do These Results Seem Reasonable

[Midwest Player]

Last night I pulled an all-nighter playing a promotion that required 1,000 hands of table game action at a min of $100 a hand or more to qualify for a $2,000 prize. The action was mostly on Spanish 21 (99.66% payback to player) and blackjack (99.62% payback to player). I flat betted $100 the entire time and played basic strategy. On Spanish 21 I rescued more hands than basic strategy says to so my basic strategy wasn't perfect but was close.

Anyway, here are the swings that happened. Do they seem reasonable? Started off, and right away got about $500 ahead. Then lost about $1,400. Slowly grinded back to about $900 ahead from buy in. Then all hell broke loose or as BJGenius007 says they turned on beast mode. I went from high of being $900 ahead to a loss of $2,600 a $3,500 swing. Then actually did another buy-in at this point, and I thought my goose was cooked. Believe it or not I then started on a comeback and came all the way back to actually being about $900 ahead again. Game then turned again and with less than $10,000 to play I slowly lost $1,900. I finished the promotion down about $1,000. I should have only lost about $500. Do these swings seem reasonable or are they way out of line?

[21forme]

On Spanish 21 I rescued more hands than basic strategy says to so my basic strategy wasn't perfect but was close.

So you were playing incorrectly and wonder why you lost more than theo? And in the short term?

[BJGenius007]

Last night I pulled an all-nighter playing a promotion that required 1,000 hands of table game action at a min of $100 a hand or more to qualify for a $2,000 prize. The action was mostly on Spanish 21 (99.66% payback to player) and blackjack (99.62% payback to player). I flat betted $100 the entire time and played basic strategy. On Spanish 21 I rescued more hands than basic strategy says to so my basic strategy wasn't perfect but was close.

Anyway, here are the swings that happened. Do they seem reasonable? Started off, and right away got about $500 ahead. Then lost about $1,400. Slowly grinded back to about $900 ahead from buy in. Then all hell broke loose or as BJGenius007 says they turned on beast mode. I went from high of being $900 ahead to a loss of $2,600 a $3,500 swing. Then actually did another buy-in at this point, and I thought my goose was cooked. Believe it or not I then started on a comeback and came all the way back to actually being about $900 ahead again. Game then turned again and with less than $10,000 to play I slowly lost $1,900. I finished the promotion down about $1,000. I should have only lost about $500. Do these swings seem reasonable or are they way out of line?

Since you flat bet, it is very unreasonable. Sometimes I test flat bet, it is very hard to lose or win 10 units. The results always pull you back to the flat line. Then adding the spread even just modest one, you can see your chips growing.

[Gronbog]

Do these swings seem reasonable or are they way out of line?

You don't say what the balance of hands played was for each game but in the end, it doesn't matter with regard to this question. The answer is "yes", these results are very reasonable. It sounds like a 6 or 8 deck blackjack game with S17 DAS and LS and a 6 or 8 deck S17 Spanish game. Standard deviation for the blackjack is about 1.14. For 1000 rounds at $100, the standard deviation is about 1.14 x sqrt(1000) x $100 = $3,605 (originally posted incorrectly as $11,400). The standard deviation of Spanish 21 is even higher (about 1.19 and you made it even worse with your misplay), so the standard deviation for your session is even higher than that. Your swings of +/-$3500 are only about 1 standard deviation. Your final result of only $500 less than expected is tiny.

On Spanish 21 I rescued more hands than basic strategy says to

Why in the world would you do this? Very costly and it's the simplest part of the strategy. I now have my doubts whether you played the rest of the Spanish basic strategy correctly.

[PinkChip]

Standard deviation for the blackjack is about 1.14. For 1000 rounds at $100, the standard deviation is about 1.14 x sqrt(1000) x $100 = $11,400.

But 1.14 x sqrt(1000) x $100 = $3605, not $11,400. Am I missing something?

[Midwest Player]

You don't say what the balance of hands played was for each game but in the end, it doesn't matter with regard to this question. The answer is "yes", these results are very reasonable. It sounds like a 6 or 8 deck blackjack game with S17 DAS and LS and a 6 or 8 deck S17 Spanish game. Standard deviation for the blackjack is about 1.14. For 1000 rounds at $100, the standard deviation is about 1.14 x sqrt(1000) x $100 = $11,400. The standard deviation of Spanish 21 is even higher (about 1.19 and you made it even worse with your misplay), so the standard deviation for your session is even higher than that. Your swings of +/-$3500 are only about 1/3 of one standard deviation. Your final result of only $500 less than expected is tiny.


Why in the world would you do this? Very costly and it's the simplest part of the strategy. I now have my doubts whether you played the rest of the Spanish basic strategy correctly.

Thanks Gronbog. I guessing about 80% play on Spanish 21 and about 20% on Blackjack. The games are S17. Spanish 21 has surrender, but the blackjack games don't. I believe the only hand you surrender in Spanish 21 is Ace against 17. So surrender is pretty much a non issue in Spanish 21. I seem to always do better on Spanish 21.

I have the Wizard of Odds basic strategy for Spanish 21 open on my computer right next to the game. If I'm unsure about any play I can look it up in just a click of the mouse. It is just that I have gotten killed so many times doubling down and getting a small card only to have the dealer make his hand especially against 2 or 3.

[Midwest Player]

Is this true? From Automatic Monkey.
https://www.blackjackinfo.com/commun...k.9171/page-11

"SP21 has an intrinsically lower standard deviation than BJ, because of the double down rescue rule and the fact that we are hitting a lot more stiffs, resulting in more pushes."

[Gronbog]

But 1.14 x sqrt(1000) x $100 = $3605, not $11,400. Am I missing something?

No you're right. In my head sqrt(1000) was 100. Brain cramp!

This still makes MWP's results completely ordinary.

[21forme]

First you say this:

On Spanish 21 I rescued more hands than basic strategy says to so my basic strategy wasn't perfect but was close.

And then you say this:

I believe the only hand you surrender in Spanish 21 is Ace against 17. So surrender is pretty much a non issue in Spanish 21.

Which is it?

Are you surrendering 12-16 v 8-A after doubling?

[Gronbog]

Is this true? From Automatic Monkey.
https://www.blackjackinfo.com/commun...k.9171/page-11

"SP21 has an intrinsically lower standard deviation than BJ, because of the double down rescue rule and the fact that we are hitting a lot more stiffs, resulting in more pushes."

I've never seen anyone claim this. The claim is always that the variance (standard deviation) is higher, which I've seen in my own work. The s.d. of 1.19 was from my own work for an 8 deck S17 Spanish game where bonuses (but not the super bonus) are paid after splitting.

That link doesn't work for me. There are other factors in play as well. We double less, which also would tend to decrease s.d., but there are the bonus payouts which would tend to increase it. Some of the reason for hitting more stiffs is in pursuit of these bonus payouts. I've never looked into how much the super bonus contributes to s.d.

However, I now realize that the s.d. of 1.19 that I quoted is for flat betting but with an index strategy (not Walker's). Serves me right for trying to answer quickly. Walker quotes 1.17 as the s.d. for S17 Spanish 21.

[PinkChip]

OK, thanks for clarification :-)

[Midwest Player]

First you say this:


And then you say this:


Which is it?

Are you surrendering 12-16 v 8-A after doubling?

Surrender and Rescue are two different things in Spanish 21. You can surrender only on you first two cards after dealer checks for blackjack on an Ace. Rescue only comes into play if you double down. I said I rescue more than than basic strategy calls for. Surrender on s17 game is recommended only with 17 against Ace.

[21forme]

To me, they are the same thing. You get half your bet back if you surrender or rescue your hand. You still haven't explained what you meant when you said, "I rescued more hands than basic strategy says to so..."