Thursday, January 22, 2009

Para quem quer levar o Omaha mais a sério!!!

HUTCHISON OMAHA POINT SYSTEM
The purpose of this system is to provide a simple means of evaluating starting hands in Omaha poker. It was developed in several steps:

First, Mike Caro's Poker Probe software was used to determine the win percentage for various four card combinations when played against nine opponents. This was accomplished via a Monte-Carlo type simulation with a minimum of 50,000 hands being dealt for each starting hand. The assumption made in this type of simulation is that each hand is played to the finish. This is, of course, an unreasonable expectation, but , in the absence of detailed knowledge of each player's starting requirements, method of play, etc., it is the best means of approximating a hand's strength and earning potential.

Secondly, a number of components were examined in an effort to determine their relative contribution to the value of each starting hand. Eventually, it was decided that the primary determinants of good Omaha starting hands related to the rank of the cards and whether or not they were paired, suited, or connected.

Finally, a type of regression analysis was conducted to try and determine the relative weighting of each of these factors. The system that follows is the result of quantifying the contribution made by each of these various components.

Once the calculations are made, the resultant point total, WHEN DIVIDED BY TWO, is an approximation of the actual win percentage for a particular hand--when played to the finish against nine opponents. The correlation between point totals and win percentages, while not representing a one-to-one correspondence is, nevertheless, quite high. In fact, in about 70% of the cases the actual win percentage will be within just one point of the total points awarded by this system. This means that if the system indicates that a given hand earns, say, 40 points, you can be quite confident that the actual win percentage for this hand is between 19 and 21 points. It is very likely to win more often than a hand with 38 points and almost certain to outperform a hand with 36 points.


STEPS IN CALCULATING POINT TOTALS


FIRST, to evaluate the contribution made by suited cards, look to see if your hand contains two or more cards of the same suit. If it does, award points based upon the rank of the highest card. Repeat the procedure if your hand is double suited.

If the highest card is an ACE award 8 points
If the highest card is a KING award 6 points
If the highest card is a QUEEN award 5 points
If the highest card is a JACK award 4 points
If the highest card is a TEN or a NINE award 3 points
If the highest card is an EIGHT award 2 points
If the highest card is SEVEN or below award 1 point.

If your hand contains more than two cards of the same suit, deduct 2 points.


SECOND, to factor in the advantage of having pairs,

If you have a pair of ACES award 18 points
If you have a pair of KINGS award 16 points
If you have a pair of QUEENS award 14 points
If you have a pair of JACKS award 13 points
If you have a pair of TENS award 12 points
If you have a pair of NINES award 10 points
If you have a pair of EIGHTS award 8 points
If you have a pair of SEVENS or below award 7 points

Award no points to any hand that contains three of the same rank.


THIRD, when your hand contains cards capable of completing a straight it becomes more valuable. Therefore, If your cards contain no more than a three card gap, add the following points:

For FOUR cards, add 25 points

For THREE cards, add 18 points

For TWO cards, add 8 points

From these totals, subtract two points for each gap, up to a maximum of six points.

To account for the special case represented by ACES, deduct four points from the above totals when an Ace is used. This is necessary because an Ace can make fewer straights. However, when your hand contains small cards that can be used with an Ace to make a straight, the hand's value increases. Therefore, when your hand contains an Ace and another wheel card, add 6 points. Add 12 points for an Ace and two wheel cards.



FINALLY, a determination must be made as to which hands qualify as playable. This becomes a function of how many points one decides are necessary before entering a hand. My suggestion would be to only play hands that earn 28 points or more. It can be argued that, ignoring the rake, any hand with more than a 10 percent win rate (i.e., those with 20 points or more) is potentially profitable in the long run. Still, I have the prejudice that most players, and especially those who are relatively inexperienced, would be better advised to forsake marginal hands and to focus on those that earn 28 points or more. Recalling that a random hand will win about 10% of the time in a ten-handed game, it can be seen that playing only premium combinations of 28 points or more insures that you will always have a hand that is 40% better than a random hand. The total required to raise or to call someone's raise must also be determined subjectively. I feel that 32 points is the appropriate level, so, in summary,

YOU SHOULD CALL WITH 28 POINTS OR MORE AND CONSIDER RAISING WITH 32 POINTS OR MORE



SOME EXAMPLES FOR CLARIFICATION

The hand that has the highest win percentage in Omaha contains two ACES and two KINGS and is double suited. A hand containing the AS, KS, AH, and KH would earn 54 points under this system--calculated as follows: under step one above, the two double suits headed by the two aces earn 8 points each for a total of 16 points; step two awards 18 points for the pair of aces and 16 points for the pair of kings, or a total of 34 more points; under step three, the ace-king combination earns 4 points for its straight potential. (NOTE: The two consecutive cards earn 8 points but a deduction of 4 points is made because one of the cards is an Ace.) The resultant total of 54 points, when divided by two, closely parallels the actual win percentage for the hand which is about 26.65.

Assume you have the 9S, 8S, 9D, and 8D. Step one awards a total of 6 points for the two double suits headed by nines. Under step two, the pair of nines earns 10 points and the pair of eights earns 8 points. The last step awards 8 points for the 9-8 combination. The total of 32 points, when divided by two, is the same as this hand's actual win rate of 16 per cent.

With the QS, QD,9H, and 9C, no points are earned under step one as there are no suited cards. Step two gives 14 points for the pair of queens and 10 points for the pair of eights. Step three awards 8 points for the Q-9 combination but then calls for a deduction of 4 points because of the two card gap that exists between the two cards. The final total is 28 points and, when divided by two, it again closely reflects the actual win percentage for this hand which is 14.5%.

An example of a hand that tends to be somewhat over-rated by novice players is AS, KD, QH, and TS. Under step one the hand receives 8 points for the suited ace and ten. Step two is disregarded as the hand does not contain any pairs. Step three awards 23 points for the straight potential of the four connected cards. The final total is only 31 points, making this a marginally playable hand. It actually wins about 16.2%.

Finally, consider AS, 3S, KD, 4D. Step one awards 14 points, step two awards none, and step three grants 12 points for the A-3-4 combination and 4 points for the A-K combination. This total of 30 points corresponds with the actual win rate of 15%.


NOTES

To state the obvious: many skills other than initial card selection are essential to maximizing your profits when playing Omaha. Unfortunately, these other skills do not lend themselves to easy quantification, and are thus beyond the scope of this simple mathematical approach. I do hope, though, that this system will be of help to the novice player in making the important decision about which starting hands are worthwhile.

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