delizle - 02 March 2009 07:30 PM
Say i were to bet 2 $25 dollar chips ($50 in total) on the come out roll, the roll comes and it is 4, would i then be aloud to remove one of my $25dollar chips (making the passline bet $25) and place it as odds?
The confusing thing about the “line bets” in craps (pass, come, don’t pass, don’t come) is their two-part nature. On the first roll, the bet may or may not be resolved (decided).
pass/come 7 or 11 = win
2, 3 or 12 = lose
don’t pass/don’t come 7 or 11 = lose
2 or 3 = win
12 = “push” - no decision
The essence of craps is that the two six-sided dice create 36 possible outcomes, but since you add the two numbers together, you get only eleven possible sums, 2 through 12, distributed like this
2, 12 1 each
3, 11 2 each
4, 10 3 each
5, 9 4 each
6, 8 5 each
7 6
So, seven is the most likely sum, because it can be made six different ways, and two or twelve can be made only one way each.
This means that, on the comeout (first) roll, the passline bettor has 8 ways to win, just 4 ways to lose, while the don’t-pass bettor has 8 ways to lose, 3 ways to win and one way to “push”. So the pass bettor has an advantage on the comeout roll, the don’t pass bettor a disadvantage.
If the first roll is not 7 or 11 or 2 or 3 or 12, the bet is not resolved; rather, the number rolled (4, 5, 6, 8, 9 or 10) becomes the “point”, and the dealers will put a big “ON” button behind that number on each side of the layout. Now, for this second part of the bet, the rules change completely. For the pass/come, the shooter must roll this “point” number again, before rolling a seven, in order to win. The don’t-pass bettor wins if the seven comes before the point number.
Since the seven is the most likely of all the sums, the pass bettor is more likely to lose than to win, while the don’t-pass bettor is more likely to win.
So:
comeout: pass/come more likely to win than lose; don’t pass/don’t come more likely to lose than win
point established: pass/come more likely to lose than win; don’t pass/don’t come more likely to win than lose
So, if you have made a $50 pass bet, and a point number is rolled, the casino has given you that 8:4 chance to win on the comeout; they are not going to let you take any money off that bet, now that the odds are in the casino’s favor.
By the same token, you cannot make a don’t pass bet after a point has been established, because you have not subjected your money to the 3:8 disadvantage on the comeout. Some people try to do this; it is cheating.
On the other hand, the casino WILL let you make a pass bet after a point has been established. Why? Because the bet is now more likely to lose. The player has missed out on the comeout roll. After a point has been established, the pass/come player has only about a 40% chance to win, but the casino pays only even money, not a good deal at all.
By the way, in order to shoot the dice, the player must have at least a minimum bet on the pass or don’t pass. The shooter can shoot the dice until he/she “sevens out”, i.e. establishes a point and rolls a seven before repeating that point number. This is called a “hand”.
Here’s something called “the perfect 1980” that represents the “expected” distribution of 1980 pass or come decisions:
win on comeout 440
lose on comeout 220 660 comeout resolutions
win on point 6 or 8 250 1320 point resolutions
lose on point 6 or 8 300 536 point wins
win on point 5 or 9 176 784 seven-out
lose on point 5 or 9 264
win on point 4 or 10 110
lose on point 4 or 10 220
——-
1980
One can glean a lot of information from “the perfect 1980”.
one-third of the decisions come on the comeout roll, of which twice as many are winners as losers
two-thirds of the decisions come after a point is established
after a point is established the average probability of making the point is .406 (536/1320)
before the comeout roll, the probability of a seven-out is .396 (784/1980)
the average number of decisions per “hand” is 2.526 (1980/784)
Since the average number of rolls for a decision is 3.375, the average “hand” lasts 8.525 rolls.
There is a near-mirror-image distribution for don’t pass/don’t come decisions, with the comeout looking like this:
440 lose comeout
165 win comeout
55 push on comeout
Cheers,
Alan Shank