7craps
7craps
Joined: Jan 23, 2010
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April 23rd, 2013 at 12:12:38 PM permalink
Quote: Jimbo

I agree with you that the house edge for the Field is 2.78%. The house edge for placing the 6 and 8 is 1.52%. The house edge for placing the 9 is 4.00%. I don't think there is any way mathematically possible to combine those bets to arrive at a combined lower house edge.

But as DeMango reminded me, I've only been on the Forum a month, so I am undoubtedly mistaken.

Remember
we can calculate the house edge as "per roll"
or "per bet resolved".
Many times they are the same but not for this Iron Cross example.

First keep these formulas in mind
ev=$bet(action)*He (action can be per roll or resolved and can be a weighted average)
he=ev/$bet
$bet=ev/he


-$2.08333/$205 = -1.01626% house edge per roll per $205 of action
ev/$ bet (action per roll)

-$2.08333 = EV
$205 = action per roll (NOT $ bet resolved)
-1.01626% = HE per roll

so 100 rolls = $20,500 total action (not resolved action)
***ev = -$208.33***
$20,500*-1.01626%



Now per action resolved (average resolved $ bet per roll)
f	35	0.444444444	15.55555556
5 85 0.111111111 9.444444444
6 95 0.138888889 13.19444444
8 95 0.138888889 13.19444444
7 205 0.166666667 34.16666667
total 85.55555556

So, the average resolved $ Bet per roll = $85 5/9

ev / total resolved action per bet

-2.083333333 / 85.55555556 =
-0.024350649 = -2.4350649% house edge
this looks right because per bet resolved the Field = 2.78%; the 5 = 4% and 6&8 = 1.51%
So it has to be between 1.51% and 4% and it is per average $bet resolved

100 rolls = 8555.555556 total $ resolved
8555.56 * -2.4350649% = -$208.33

SAME EV as the -1.01626% but different action

The -1.01626% is over MORE action


I find it easier to use the per roll per action over many rolls than the resolved $bet per roll.
Some may find that easier.

just do not mix up your types of action.
Total action per roll vs resolved action per roll
are apples and oranges.

here is a link to the $22 Iron Cross thread that went over the same concept
http://wizardofvegas.com/forum/questions-and-answers/math/3573-house-vig-on-anything-but-7-rdutch/

Two different house edges produce the SAME EV because of different action
winsome johnny (not Win some johnny)
Jimbo
Jimbo
Joined: Mar 11, 2013
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April 23rd, 2013 at 12:50:34 PM permalink
Quote: 7craps

First keep these formulas in mind
ev=$bet(action)*He (action can be per roll or resolved and can be a weighted average)
he=ev/$bet
$bet=ev/he

Thank you for mentioning "weighted average." That clears up something for me.

I mentioned that I read elsewhere that the house advantage for the "Anything But Seven" bet strategy is 3.97% but I did not figure out how that was arrived. Now I know thanks to your remark. The author first calculated the average weighted gain with the resulting net returns and then converted that financial data to the house vig in order to compare the bet with other bets on the table.
tupp
tupp
Joined: Feb 9, 2012
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April 23rd, 2013 at 1:12:38 PM permalink
Quote: Jimbo

I suppose if the $50 don't pass bet that you have made is a "life altering" amount--in the sense that the loss of $50 is something that you could not sustain--then only in that instance would you even remotely consider hedging the bet.


I wasn't asking for philosophy nor for speculation into one's motivation -- I was asking about the house edge with the specified flat bet and hedge.


Quote: Jimbo

To begin with, on the don't pass with 4 as the point, you are already a 2 to 1 favorite to win the bet. There is nothing you can do to improve those odds. You can take a better advantage of your favorable position by laying odds against your don't pass bet. You are still the 2 to 1 favorite regardless.


The 2 to 1 probability exists no matter how one has the 4 in a "don't" bet. I was asking about house advantage.


Quote: Jimbo

When you buy the 4 for $30, all you've done is create a second, separate bet with its own individual house advantage. In this case 4.76%. Combining the bet for buying the 4 with your original don't pass bet, all you've done is to take away from your initial advantage over the house.


Really?

So, in the aforementioned scenario, you would maintain that all I have done was to add another separate bet -- I have not locked-in a profit of ≧ $19?


Quote: Jimbo

If you goal is to be paid "something" regardless of the outcome of the resolution of the point number (4 in this case), then this is certainly a way to achieve that goal.


Wouldn't that way change one's house edge from a negative percentage less than 100 (on the standing "don't" flat bet) to a "lead pipe cinch" (a house edge of -100%)?


Quote: Jimbo

But as a "strategy," this would not make any sense, since the reason you are the 2 to 1 favorite with the 4 as the point is that you succeeded in getting to the point, i.e. you did not lose the don't pass bet on the come out throw when you are at a clear disadvantage.


So, locking-in a profit doesn't make any sense?


Quote: Jimbo

Once you get pass the come out roll (on a don't bet), enjoy your advantage over the house. Don't diminish it.


I would say that there is another advantage over the house when one has a "don't" flat bet up on a number -- the advantage is that one can lock-in profits with a hedge.
ahiromu
ahiromu
Joined: Jan 15, 2010
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April 23rd, 2013 at 1:29:29 PM permalink
You know what a great field bet strategy is? When your chip count is half that of your buy in, put everything on the field.
Its - Possessive; It's - "It is" / "It has"; There - Location; Their - Possessive; They're - "They are"
Jimbo
Jimbo
Joined: Mar 11, 2013
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April 23rd, 2013 at 2:56:26 PM permalink
Quote: Jimbo

When you buy the 4 for $30, all you've done is create a second, separate bet with its own individual house advantage. In this case 4.76%. Combining the bet for buying the 4 with your original don't pass bet, all you've done is to take away from your initial advantage over the house.

Quote: tupp

Really?

So, in the aforementioned scenario, you would maintain that all I have done was to add another separate bet -- I have not locked-in a profit of ≧ $19?

I did not mean to be dismissive of your initial question or appear to be philosophical. Sorry.

Yes, I do believe that what you've done here is to create a second, separate bet when you bought the 4. In my view, the advantage you have on the don't pass bet is reduced by the cost or house edge for buying the 4.

I suppose someone may point out to me that my way of thinking is no different if you paid the house commission and bought the 10 instead of the 4 (while 4 is the point). Certainly buying the 10 does not assure you of a profit on the 4, but in terms of overall house advantage or vig, are not both scenarios the same from a strict mathematical perspective? In each scenario, you still have two bets. On the one hand you have bought the 4 with your don't pass bet. On the other hand, you have bought the 10 with your don't pass bet. The fact that one scenario locks in the profit on the don't and the other scenario does not lock in a profit does not change, mathematically, the cost or house vig overall.

If you look at the cost of buying the 4 as "insurance" to "lock-in" your profit, you are right.

Though you have locked in a profit, you have, at the same time, lost out on the opportunity of a greater profit by not buying the 4. By not buying the 4, you are exposed to losing your don't line bet altogether. Which, to a great degree, defines what a hedge is.

But whether this "makes sense" is a personal decision based on whether a player believes the cost of insurance is worth it. You also are right, discussing this from a philosophical point of view (as if one way is right and the other way is wrong) is irrelevant. To each is own.

I also fully agree with you that when you are in the enviable position of having a don't flat bet, after the point is established, there is the opportunity to lock in at least "some" of the profits with a subsequent bet.

As to how you accurately determine the house edge or overall costs of such a strategy is whether you include the exposure of a loss on the come-out roll or not.
DeMango
DeMango
Joined: Feb 2, 2010
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April 23rd, 2013 at 3:28:16 PM permalink
Quote: Jimbo


When you buy the 4 for $30, all you've done is create a second, separate bet with its own individual house advantage. In this case 4.76%.q]

Not where I play! Pays $59, vig after win.

When a rock is thrown into a pack of dogs, the one that yells the loudest is the one who got hit.
Jimbo
Jimbo
Joined: Mar 11, 2013
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April 23rd, 2013 at 3:39:20 PM permalink
You are right DeMango. I am accustomed to the practice in a number of casinos where I play in which you pay the vig up front whether you win or lose. The house edge of 4.76% that I mentioned is based on that. I believe the house edge when the vig is only paid on the win is 1.67%.
nezbit
nezbit
Joined: Apr 1, 2013
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April 24th, 2013 at 11:36:14 AM permalink
so my math was right for the Iron Cross?


can we find some "dice controllers/influencers" who can take this edge in our favor and go break some casinos?



Also can someone please explain to me what system the DI/DC use? Like i have stated before the iron cross is about the only one that makes sense to me, since they are avoiding the 7. i really dont get why you would ever want to waste a roll and not get paid. Might as well get paid on every throw except for the one they are "pro" at dodging which is the 7.

Remember if you do the iron cross to make sure on the come out roll you tell the crew all your bets are working. I did this bet once and forgot to tell them that an 8 was rolled and they took my field and didnt pay my 8. obviously i raised hell and was quickly shut down and told its always assumed off. i told them "why the fuck! would i ever want it off if i dont have a line bet?" sure enough i lost the argument so dont make the same mistake and good luck.
tupp
tupp
Joined: Feb 9, 2012
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April 24th, 2013 at 11:49:40 AM permalink
Quote: nezbit

Also can someone please explain to me what system the DI/DC use? Like i have stated before the iron cross is about the only one that makes sense to me, since they are avoiding the 7.


It is generally held that DIs try to avoid loss rolls. So, on the comeout roll with a pass line bet, they usually try to avoid the craps numbers. A 5-2/4-3 set is common on the comeout. Of course, after a point is established, one tries to avoid the seven.
nezbit
nezbit
Joined: Apr 1, 2013
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April 24th, 2013 at 11:58:52 AM permalink
when you bet the DP line and roll a 4, you have already given up an edge by fading the 7 or 11 which is 9/36 outs 25% of possible outcomes. Once you do this and you hedge you are negating your even better odds of rolling the 7 (6/36) vs the 4 (3/36). when you hedge you guarantee yourself money sure, but you just add extra house edge, you are essentially just paying the house free "juice"

4 point
$50 DP line
**(omitting any odds before this)**
you will win this bet 6/36 and lose 3/36
6*50/36 = 8.333
3*-50/36 = -4.166
net = 8.333 - 4.166 = 4.166

you can expect to make +$4.166 per throw with this set up


knowing this lets add a $30 bet the the "place bet" 4, (yes i know buy is better bet, but this is to keep math simple and show you difference)

Place 4 $30
pays 9/5 or $54

now lets change the numbers above with our newly added information

7 roll (6*($50-$30)/36) = 6*20/36 = 3.333
4 roll (3*($54-$50)/36) = 3*4/36 = 0.333
net 3.333 - 0.333 = $3.000

you can now expect to win only $3 per throw instead of $4.166 as showed above. you lose $1.66 by hedging your bet (long run of course), yes i understand some people would rather have guaranteed money now, then beat the "FOREVER" long run.

i can keep going with this math but i just tried to keep it basic.




one thing you never ever do and i have seen people do "NEVER PULL YOUR DP LINE BACK DOWN AFTER POINT IS ESTABLISHED" I have seen people pull line back when a 6/8 hits. This is never correct as you always have a better chance of rolling a 7.

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