| Posted by: Sirius at July 17, 2003, 4:41 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
For obvious reason, you normally have a lower return for each dollar wagered when you double. You only double because you will make more profit on that hand in the long run by doubling even though you have more chance of winning the hand if you hit normally.
If there weren't any pushes in Blackjack then doubling would be the only differences to BS (so no hitting and standing differences like the 16 10 example). This is because BS would maximize the wins. Losses are only worth half the alue of wins even with a 100% rebate so any rebate under 200% can't catch up.
If the normal EV for a particular hand is close to 100% for both taking 'one more card' and hitting as per BS, then loss rebates will probably mean you should double since rebates almost increase the EV linearly because the number of losses would be about equal between doubling and hitting the hand if the EV was so close. For example if taking one more card has a 101% return and hitting as per BS has a 105% return then the rebat... | | Read Entire Entry |
| Posted by: Clayman at July 17, 2003, 3:39 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by Sirius:
Hit as per BS: Win=50%, Push=8%, Lose=42% Take one card only: Win=48%, Push=7%,Lose=45%
So, if you hit, after 100 $1-hands with a 10% rebate, you end up with $8+(.1*42 losses)=$12.20
If you double 100 hands, you end up with $6+(.2*45 losses)=$15.00
In the first case I have a 12.2% return on a $100 investment, in the second a 7.5% return on my $200 investment, although I do have more absolute dollars.
So, if I stick to BS, after investing the same amount of money, I will be better off.
If I had to play one hand, I would go for the highest return on my dollar.
How did you figure the number of ties anyway? A sim or those computer programs you write? Or did you just adjust to approximate the actual EV of this particular hand? I only ask because I would have no idea how to figure that out. All I think I know is that a 20-20 push is the most common tie.
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| Posted by: Sirius at July 17, 2003, 1:42 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Here are approximate figures for 9 2
Hit as per BS: Win=50%, Push=8%, Lose=42% EV=108%
Take one card only: Win=48%, Push=7%, Lose=45%, EV=103% which is 106% in terms of the original wager that is doubled, if you see what I mean.
where x is the rebate proportion (percentage divided by 100),
103+45x will give the EV after rebate for hitting one more card (subtract 100 and double it to get the percentage profit on the original wager).
108+42x is the return for hitting. The equation for the EV after rebate is just the normal EV plus 'x' times the number of losses.
To find the minimum rebate to affect the strategy (easier in this case if you subtract 100 from the normal EV figures 108 and 103): 8+42x=2[3+45x]=6+90x,
so 2=48x or x=1/24 i.e. the rebate only needs to be little over 4% for doubling to be better.
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| Posted by: do_not_drink_and_gamble at July 17, 2003, 12:57 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Sirius clarifies
one important point:
the EV is not the same thing
as the probability to win.
That is why I use doubles
as natural examples
of changes in the optimal strategy
caused by loss insurance.
It is obvious without
any simulation software
that if say 50% of my losses are reimbursed
and I want to play precisely one hand,
then I should double 9 against 2.
Bonuslover,
if you dont agree with that,
then you have no common sense
and should be ashamed of yourself.
If 20% percent is reimbursed then
it might be less obvious but
you should still double.
Hence, the following
statement is true:
loss insurance
affects the optimal strategy
if you have to play precisely one hand.
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| Posted by: Sirius at July 17, 2003, 11:48 am | | Topic: Casinos with loss insurance Forum: Winner Online |
As I said earlier, if there weren't any pushes, then obviously you would always win more playing BS but it isn't as simple as that. Pushes contribute to the EV. In the example I gave of 16 (not two 8's obviously) 10 then you would only need a rebate of 3.6% (actually 100/28 thanks to a bit of algebra) to change the right decision.
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| Posted by: Sirius at July 17, 2003, 11:37 am | | Topic: Casinos with loss insurance Forum: Winner Online |
With 90% rebate it's still better to stay 113.32% 110.9%
With 50% rebate it's still better to stay. 81.8% 80.5%
With 10% rebate it's still better to stay.
51.28% 50.1%
With no rebate (just to show my figures make it better to hit).
42.4% 42.5%
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| Posted by: Sirius at July 17, 2003, 11:13 am | | Topic: Casinos with loss insurance Forum: Winner Online |
It's not just a small difference. You win about 18.5% of the time if you hit and push 5.5% (pushes contribute to EV the same as half a win and losses normally contribute nothing unless there is a rebate). If you stay you will win about 21.2% of the time (when the dealer busts) but the rest of the time you lose.
With a 100% rebate it would be far better to stay. A difference of between 121.2% return for staying and 118.5% for hitting (small error here before!).
[This message has been edited by Sirius (edited 07-17-2003).]
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| Posted by: Clayman at July 17, 2003, 10:42 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by hhcfreebie:
Refund of 100% means a "loose" is a "push". Push is still worse than a win.
Refund 200% means a "loose" is a "better win". That's why BS will reverse itself after 200%, not 100%.
Go back to my example of 9,7 s 10 and use 101% rebate - you have 5.37 if you stand and 5.35 if you hit after your losses are re-imbursed 101%.
It's all ery silly because obviously no casino is going to give you back more money than you lose. If they did, you would play to lose because the more you lose, the more you would win.
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| Posted by: Sirius at July 17, 2003, 10:41 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by hhcfreebie:
Refund of 100% means a "loose" is a "push". Push is still worse than a win.
Refund 200% means a "loose" is a "better win". That's why BS will reverse itself after 200%, not 100%.
If you stay on 16 against a 10 you will win more often than if you hit but BS is to hit (due to pushes- did you read the example I gave?). So with a 100% rebate on losses it's better to stay.
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| Posted by: hhcfreebie at July 17, 2003, 8:48 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by Clayman:
No, I think BS would reverse itself at anything over 100%.
But we do agree that no rebate under 100% will change a BS decision.
Refund of 100% means a "loose" is a "push". Push is still worse than a win.
Refund 200% means a "loose" is a "better win". That's why BS will reverse itself after 200%, not 100%.
------------------
online gambling "watcher".
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| Posted by: Sirius at July 17, 2003, 6:31 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by hhcfreebie:
Urr... I just ran a simple simulation and the result is so predictable. Take 7,9 s 10 for example, the play strategy never change when the refund is 1-100%. Only when the refund is more than 200% then the play strategy will change.
The reason is so obvious and I feel silly to even run a simulation to prove a well known fact: By play BS you win more often and loose less. No matter how much you get refund a loose is still less desired than a win. (unless the refund is 200% then the "loose" become "win")
The EV is based on the odds of win, lose and push. For example, it is marginally better on average to hit a two card 16 against a 20 but you still win more often if you stay. The EV is only greater for hitting due to the pushes/ties (which are impossible if you don't hit). If you also get a refund on losses (on every hand), the loss would not be 100% so some decisions may change due to the pushes coming into the EV cal... | | Read Entire Entry |
| Posted by: Clayman at July 17, 2003, 4:31 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by hhcfreebie:
Only when the refund is more than 200% then the play strategy will change.
No, I think BS would reverse itself at anything over 100%.
But we do agree that no rebate under 100% will change a BS decision.
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| Posted by: hhcfreebie at July 16, 2003, 11:59 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Urr... I just ran a simple simulation and the result is so predictable. Take 7,9 s 10 for example, the play strategy never change when the refund is 1-100%. Only when the refund is more than 200% then the play strategy will change.
The reason is so obvious and I feel silly to even run a simulation to prove a well known fact: By play BS you win more often and loose less. No matter how much you get refund a loose is still less desired than a win. (unless the refund is 200% then the "loose" become "win")
------------------
online gambling "watcher".
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| Posted by: Clayman at July 16, 2003, 6:02 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by hhcfreebie:
Some of the hand might be different than BS such as 16 s dealer's 10.
Most hands should still be the same as BS though.
I don't think there is a single hand where BS would change, no matter what the loss-insurance rate is as long as it's less than 100%. Certainly, doubling 17 or 18 s 2 would be suicide. What is your reasoning here?
Take 9,7 s 10 with a 20% loss rebate (multi-deck, standard rules), a ery close play. EV of hitting is -.535,EV of standing is -.537.
If you stand on this hand 1000 times betting $1/hand, you lose $537 and get a rebate of $107.40 for a net loss of $429.60. If you hit 1000 times, you lose $535 and get a rebate of $107.00 for a net loss of $428.00. You still lose less by hitting - same as BS. You only succeed in reducing your losses by 20% ($1.60 s $2)
There is no case where BS would change, no matter how close the plays are. I think all you are really doing overall is reducing the HA by the l... | | Read Entire Entry |
| Posted by: hhcfreebie at July 16, 2003, 4:13 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Now I get your idea, you assume casino would refund every hand you play when you loose.
In that case the rule is altered, when you loose you only loose part of your bet. Actually if they refund more than 200% bet when you loose you will try to loose every hand, thus you will play "anti-BS".
The BS difference really depends on how much you get refund per hand. It's similiar to card counting and alter BS based on true count.
Since you didn't get refund every hand, instead they refund your loose after a period of time. I still think BS is close to optimal play most of the time.
Like Bonuslover said, go try casino8 they refund 5-7% per day so you can get refund every hand. Some of the hand might be different than BS such as 16 s dealer's 10.
Most hands should still be the same as BS though.
I really don't think double 17, 18 on dealer's 2 is a good idea even with 50% refund.
------------------
online gambling "watcher".
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| Posted by: bonuslover at July 16, 2003, 12:40 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
You know what, go register with casino8online.com, they refund losses everyday. Put your idea to work for 1 year and come back to tell us the results.
[This message has been edited by bonuslover (edited 07-16-2003).]
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| Posted by: do_not_drink_and_gamble at July 16, 2003, 11:07 am | | Topic: Casinos with loss insurance Forum: Winner Online |
In this particular case,
for example,
when you want to make one
bet a month,
the optimal strategy will be different
from the basic one.
For example, you should double 9, 17, and 18 against 2
and make some other agressive plays
that are not recommended
by the basic strategy.
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| Posted by: bonuslover at July 16, 2003, 10:26 am | | Topic: Casinos with loss insurance Forum: Winner Online |
READ
First of all, the casino is likely to refund your NET losses once in a month, not immediately after you lose any single hand. The only way to abuse this system is to place only 1 bet every month. If the casino refunds your losses everyday, then the best way to abuse this system is to place 1 bet everyday.
The expected return of BJ is like say 99% using best strategy. That means every bet you make you expect to lose 1% of it. Deviating from the best strategy in the first place will lower that 99%.
Dig it?
[This message has been edited by bonuslover (edited 07-16-2003).]
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| Posted by: bonuslover at July 16, 2003, 10:19 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Basic Strategy is a chart, if that's what you are referring to, then your idea of changing it because of the loss-refund is totally erraneous. No offense.
[This message has been edited by bonuslover (edited 07-16-2003).]
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| Posted by: do_not_drink_and_gamble at July 16, 2003, 10:10 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Clayman,
thanks for the first meaningful reply.
I agree that the effect is
of second order
and largely of academic interest
because the insurance never exceeds 20%.
I would analyze
the question by dynamic programming
rather than by Monte Carlo.
Bonuslover,
I used to teach STAT 101 in Caltech
but had to quit due to
drinking problems.
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| Posted by: Clayman at July 16, 2003, 3:35 am | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by do_not_drink_and_gamble:
To take an extreme case, if 100% of your losses are reimbursed, then your optimal strategy will be obviously different from the standard basic strategy.
I guess your point is, if 100% of your losses are re-imbursed, does that mean you should now double every 20 (indeed every hand) because you can't lose?
If 10% of your losses are re-imbursed and a certain play normally has an EV of 20 cents on a $1 bet if you stand, and 18 cents if you hit, is that play now a toss-up because if you hit and lose it will only cost you 18 cents after re-imbursement anyway?
Maybe, if you have some sim software and alot of time, you could figure it out. Otherwise I'd stick to regular BS like freebie says.
[This message has been edited by Clayman (edited 07-16-2003).]
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| Posted by: Bone-Us at July 15, 2003, 6:48 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
do_not_drink_and_post!
You are going to maximize the number of useLESS replies with your attitude.
[This message has been edited by Bone-Us (edited 07-15-2003).]
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| Posted by: Geoff Hall at July 15, 2003, 4:50 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Quote: Originally Posted by do_not_drink_and_gamble:
HH
you did not understand
what i was talking about.
If, say, you are plus $1000
and playing one last $100 bet,
then you should use the basic strategy
because you cannot go below zero.
However, if you are at zero (also
known as status quo),
then you wins are full,
but your losses are discounted.
Hence, the optimal strategy is modified.
Have you ever calculated the basic strategy yourself, huh?
Try that and you'll see the point.
Not only did you post this in the wrong forum but when hhcfreebie kindly offered his advice your reply seemed rather arrogant and a little insulting.
You'll find that you will increase the chances of getting useful feedback if you reply in a courteous manner and show appreciation for those who have taken the time to reply to you regardless of whether the input is useful or not.
Geoff Hall
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| Posted by: do_not_drink_and_gamble at July 15, 2003, 3:17 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
HH
you did not understand
what i was talking about.
If, say, you are plus $1000
and playing one last $100 bet,
then you should use the basic strategy
because you cannot go below zero.
However, if you are at zero (also
known as status quo),
then you wins are full,
but your losses are discounted.
Hence, the optimal strategy is modified.
Have you ever calculated the basic strategy yourself, huh?
Try that and you'll see the point.
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| Posted by: hhcfreebie at July 15, 2003, 3:02 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
This post should go to "Joker's wild".
You should never change the basic strategy based on promotion, unless the rule of the game is altered such as paying double on BJ.
How to play this kinda of promotion you ask? Bet big and set a ery high goal. Assume a near 100% return game such as BJ with 50% refund.
goal: 200%, EV: 25%.
goal: 400%, EV: 37.5%
goal: 800%, EV: 43.75%
The more often you loose, the better the EV.
(ps: Thanks to KX for the enlightment)
------------------
online gambling "watcher".
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| Posted by: do_not_drink_and_gamble at July 15, 2003, 2:38 pm | | Topic: Casinos with loss insurance Forum: Winner Online |
Many casinos offer
loss insurance.
This type of bonus will distort
the basic strategy at the status quo
point because the payoffs
have a kink there
and the formula for EV changes.
To take an extreme case,
if 100% of your losses
are reimbursed, then your optimal strategy
will be obviously different
from the standard basic strategy.
In particular, this will effect
splits and doubles (you will do
both more often).
Has anybody done any research on that?
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