AcesAndEights
AcesAndEights
Joined: Jan 5, 2012
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October 18th, 2012 at 1:53:52 PM permalink
Quote: 7craps

You can have a pencil and small notepad with you. I do it all the time.
Now, Not 120 rolls per hour unless everyone is making just one bet on a cold table.

One can calculate the Expected loss and standard deviation from Alan's two posts

http://wizardofvegas.com/forum/questions-and-answers/math/1636-what-is-my-average-bet/#post12528

http://wizardofvegas.com/forum/gambling/tables/1130-how-many-come-bets-is-too-many/5/#post8852

My sims show the number of resolved come bets per resolved pass line bet for max 3 come bets made is:
per 1000 rolls: 1.85
per 100 rolls: 1.83
Alan for 200 rolls is 1.91
We are close.
I did a few million sessions where he did only 2k.

The EV for max 3 come bets should be the easy calculation.
Do not stop there.

EV by itself can be very misleading and does not lead one to make very good decisions for playing time,
bet size, bankroll requirements to the bet sizes for example.

Hate to see you quit at the EV value and as you are walking away
you keep hearing the word "Winner", "7Winner", "Front line winner", "Coming out, same hot shooter"

The Standard Deviation will tell you how far from the mean (EV)
you can expect to be after a number of rolls/bets made and
your Risk of Ruin for a number of bets or rolls and a starting bankroll.

IMO, If you show your work first, I will think others may show theirs after.
Have fun!


Okay 7craps, taking this data provided by goatcabin in the linked post, if I'm going Pass + maximum 3 come bets, my average units on the table will be 2.91.
I'm going to use this number and go with
$25 * 2.91 * .0042 * 100 = $30.55/hour expected loss.

Anyone want to take a stab at that 2.91 number if you're playing DP/DC? I guess I have a Windows machine at work now, I could go and grab WinCraps...
"So drink gamble eat f***, because one day you will be dust." -ontariodealer
teddys
teddys
Joined: Nov 14, 2009
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October 18th, 2012 at 2:25:54 PM permalink
Quote: DenDexter

Good post.

I hit Vegas over the weekend. Hit $3k Royal Flush in first 5 minutes playing video poker. Great luck!
I played craps at $3 min and 10x odds. I entered with $500 and played only pass bet with max odd and 1-2 come bets with max odd. I left in 45 minutes down $450. Playing with 10x the house edge is 0.184%, however that didn't matter with the 7's appearing too often.

So I had my best luck ever in VP and worse luck ever in craps close to each other. Oh well still a great weekend and went home a winner :)

Oh, my, that is nothing. Many times I would be happy to be down only $450 playing that way. The variance in the odds bet should not be underestimated -- it is brutal, but is also what allows you to win big sometimes!

Congrats on the royal hit. I assume it was three lines of quarter play?
"Dice, verily, are armed with goads and driving-hooks, deceiving and tormenting, causing grievous woe." -Rig Veda 10.34.4
tringlomane
tringlomane
Joined: Aug 25, 2012
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October 18th, 2012 at 2:43:18 PM permalink
Quote: DenDexter

Good post.

I hit Vegas over the weekend. Hit $3k Royal Flush in first 5 minutes playing video poker. Great luck!



Dealt royal in quarter triple play? I'm trying to figure out how you can have a royal for $3k... And I easily take a -$450 craps session for that Royal. :D
7craps
7craps
Joined: Jan 23, 2010
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October 18th, 2012 at 4:13:48 PM permalink
Quote: AcesAndEights

Okay 7craps, taking this data provided by goatcabin in the linked post, if I'm going Pass + maximum 3 come bets, my average units on the table will be 2.91.
I'm going to use this number and go with
$25 * 2.91 * .0042 * 100 = $30.55/hour expected loss.

Nice work!

What is missing are the expected odds you plan on making.

I can show results for NO odds and 345X odds and 2X odds for you.
This is a fast lesson. Good MLB today. Go Tigers!

I will show how to do this per decision.

This will give one more data for the standard deviation calculations.
Since you can easily know how may bets, on average, you will make.

1) 100 rolls / (557/165) = 29.62 pass line decisions (This goes towards the EV)
557/165 = average number of rolls per pass line decision

2) 19.75 pass line odds bet (29.62*(2/3))
2/3 of the time an odds bet can bet made.

3) 29.62 * 1.91 = 56.6 average come bet decisions (This goes towards the EV)
The 1.91 is the average number of come bet decisions per pass line decision
that came from a simulation and is a little higher than what a nasty calculation shows. Close enough for what we do here.

4) 37.7 come odds bet decisions (56.6*(2/3))
86.22 total decisions for the EV calculation

Now step 5)
(Add #1 and #3 results = 86.22)
86.22 * $25 * (-7/495) = 30.48
Simple. (#bets * avg bet * House Edge = EV)

Now the Standard Deviation.
link here for formulas...
http://wizardofvegas.com/forum/gambling/tables/1213-variance-in-craps/
SD tells us how far from that -$30 we can except to end up at, as long as we have enough starting bankroll to survive the 100 rolls.
SD can also tell us how much a starting bankroll to have for our bet sizes to have a certain session Risk of Ruin or a certain net gain to our bankroll.

================================================
We NEED the TOTAL number of decisions.
29.62 + 19.75 + 56.6 + 37.7 = 143.67

1) Pass/Max3Come with NO odds: 1unit SD = 0.999900005 (or 1 rounded)
$Bet ($25) * 1 (1 unitSD) * square root of 86 -# of decisions- (9.27) = $232
A 1SD (68%) range would be -$30 +/- $232 (-$262 to +$202)
That -$30 gets buried in the range for one session.

"The probability that the session outcome will be within one standard deviation is 68.26%.
The probability that the session outcome will be within two standard deviations is 95.46%.
The probability that the session outcome will be within three standard deviations is 99.74%."

A) Add your EV and 2*SDs to get a starting bankroll that will give you about a 5% (1 in 20 bust) session Risk of Ruin.
B)Add your EV and 1*SD to get a starting bankroll that will give you about a 32% (1 in 3.1 bust) session Risk of Ruin.

For longer sessions, one MUST re-calculate EV and SD.
Easy math for Excel to do.

Quote: AcesAndEights

Anyone want to take a stab at that 2.91 number if you're playing DP/DC? I guess I have a Windows machine at work now, I could go and grab WinCraps...

I can say to subtract about .07 (by memory) from the pass/come decisions to get you close.

EV by itself, IF you know the Standard Deviation, can get you to a bankroll,
otherwise figure the SD and be happy.

Good Luck!
winsome johnny (not Win some johnny)
AcesAndEights
AcesAndEights
Joined: Jan 5, 2012
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October 18th, 2012 at 5:10:27 PM permalink
Quote: 7craps


...
Yep. The 0% house odds bet sure adds no EV but LOTS of variance/standard deviation.

A) Add your EV and 2*SDs to get a starting bankroll that will give you about a 5% (1 in 20 bust) session Risk of Ruin.
B)Add your EV and 1*SD to get a starting bankroll that will give you about a 32% (1 in 3.1 bust) session Risk of Ruin.

For longer sessions, one MUST re-calculate EV and SD.
Easy math for Excel to do.
...
EV by itself, IF you know the Standard Deviation, can get you to a bankroll,
otherwise figure the SD and be happy.

Good Luck!


Thanks man, although let the record show I didn't ask for all that work :).

I know it sounds shortsighted, but I really don't care about SD for this trip since craps is going to be a very small portion of my gambling action. I sized my trip bankroll mainly for blackjack, and am comfortable with my risk of ruin playing 10ish hours of BJ over the weekend. For craps, I really just wanted to know what my EV would be, so I can keep my expected losses in check over the LONG TERM (e.g. my lifetime of gambling).

I hadn't thought about it, but I should set a stop-loss limit for craps, so I don't lose my whole BJ bankroll before the weekend is out! I will use your EV+2*SD calculation above...only 5% chance I will hit that stop-loss. It wouldn't wipe out my bankroll, but it would hurt. Aye, there's the point of gambling, no?
"So drink gamble eat f***, because one day you will be dust." -ontariodealer
7craps
7craps
Joined: Jan 23, 2010
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October 18th, 2012 at 5:24:22 PM permalink
Quote: AcesAndEights

I hadn't thought about it, but I should set a stop-loss limit for craps, so I don't lose my whole BJ bankroll before the weekend is out!
I will use your EV+2*SD calculation above...only 5% chance I will hit that stop-loss.

I just did all the simple calculations (many steps)
for SD so one post can show how it is done for line bets with X number of come or Dcome bets.

Many others will follow and read.

only 5% chance I will hit that stop-loss...
ONLY 5% chance
means 1 in 20 session bust outs on average

Expect, on average, to bust a EV+2*SD Bankroll one time in 20 sessions.
That 1 in 20 average comes from a distribution of about 36% probability of busting 0 times in 20 sessions
64% probability of busting at least 1 time in 20 sessions
26% probability of busting at least 2 time in 20 sessions (This is 1 in 4)

Good Luck!
Hope to read about your Craps winnings in a news article!

one more item about SD.
One has the same chance of ending up 1SD as being down 1SD
or up XSD as being down XSD.
In Craps, this does not apply to any DI roll sequences.
winsome johnny (not Win some johnny)
AlanMendelson
AlanMendelson 
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October 18th, 2012 at 6:47:39 PM permalink
Quote: AcesAndEights

Note that odds don't factor in to the expected loss as they are 0 EV either way.



I have a question and I hope you will give this some thought before answering:

Do you really exclude your odds money from your "expected loss" when you play?

In all honesty, when I bet full odds I don't look at that money on the table and consider it to be a "push" or a "wash." It's either going to be money won or money lost and in all cases it is money at risk. I would like to think that if I play long enough that the odds bets will all just even-out in the end. But when is the end?

Look guys, I've been playing craps for almost 20 years and I am no where close to be even on odds bets. I probably could have bought a new car for what is considered to be a "no house advantage" bet.
WongBo
WongBo
Joined: Feb 3, 2012
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October 18th, 2012 at 6:56:00 PM permalink
That's what happens when you hitch a star to a wagon instead of the other way around

The odds bet doesn't exist without the negative expectation it is tied to
It only helps to bring the theoretical average loss down
But the amounts are so much higher your losses may seem to have increased.
Let's say you throw in 5000 a night at 1.4% just on pass line is roughly -$70
Or play 3x4x5x at .374% for 25000 pass with odds is roughly -$93.50
In a bet, there is a fool and a thief. - Proverb.
7craps
7craps
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October 18th, 2012 at 7:13:30 PM permalink
Quote: AlanMendelson

Look guys, I've been playing craps for almost 20 years
and I am no where close to be even on odds bets.
I probably could have bought a new car for what is considered to be a "no house advantage" bet.

Look Alan, I have been playing Craps for over 30 years and have a friend that has been playing for over 40 years.
We are both way down on the Place bet and Hardways,
my friend even admits more since he used to chase his losses.

The last 10 years or so, we play now to have most of our money on the odds bets, any odds bets.
We both bet pass and don't.
I still make a few $5 hardways and parlay them.
Most times with my winnings. It is entertainment.

I know for a fact my don't odds are well up after 10 years and my pass odds slightly down.
Not 0% or 0EV.
Because of variance.


The problem here is all gambling experts/writers say the house edge and the expected loss (EV) are set in stone,
the only values any gambler needs to consider, screw the variance and standard deviation,
and after any kind of length of play one can not help to be too far away from that HE% or $EV.

Most have bought into that BS because they do not understand how HE and Standard Deviation work together over N bets.
The math is too hard.
And because it is too hard and too much math,
most gamblers are lemmings and follow the leader and others over the edge of the cliff.
They do not know what really to expect!

Newsflash folks!!
There IS standard deviation for any House Edge value for any number of bets.
Pass line at 4000 bets
HE = 1.41% Everyone agrees here...
Standard Deviation of the HE = 1.58% (1unitSD/#bets^0.5)(0.9999/63.2455532)
1.58% * 3 is now the range around that 1.41%

Learn about EV and SD.
Life's outcomes will become less of a surprise.
winsome johnny (not Win some johnny)
7craps
7craps
Joined: Jan 23, 2010
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October 18th, 2012 at 7:51:23 PM permalink
Quote: WongBo

That's what happens when you hitch a star to a wagon instead of the other way around
The odds bet doesn't exist without the negative expectation it is tied to
It only helps to bring the theoretical average loss down
But the amounts are so much higher your losses may seem to have increased.

Yes, but only due to variance and not house edge when one compares equal action.

Quote: WongBo

Let's say you throw in 5000 a night at 1.4% just on pass line is roughly -$70
Or play 3x4x5x at .374% for 25000 pass with odds is roughly -$93.50

Nice example.

How about this example.

Let's say you throw in $5,000 a night at 1.4% just on pass line is roughly -$70 EV
Or play 3x4x5x at .374% for $18,717 pass with odds is roughly -$70 EV

Same EV... Really???

Same Entertainment??
NOT!!

Way more money bet, risked.

If the same bankrolls were risked,
the 345X odds player has a way higher probability of ending a session up than the player with no odds.
Most better understand this fact of Craps play.

Too easy just to get stuck on the EV and EV only.

"Hey, I was only supposed to lose freekin' $70 playing the best way.
Line plus Odds.
S**t!
Better to go back to just Place all the numbers, hardways and parlay horn bets.
No more odds bets for me. I never lose just freekin' $70.
I can win more and have way more fun playing this way than losing just freekin' $70"

See you all at the Craps tables
Have a Nice Day
winsome johnny (not Win some johnny)

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