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7.2.4 Modeling Abstraction

In the above discussion, it is suggested that when we maintain weight arrays for our opponents we only maintain all known possible cases (for the flop 1,081 cases of the original 1,326 since we hold two known cards). However, when we compute EHS' for an opponent in the re-weighting function, what do we use for the weight array? Our opponent does not know the two cards we hold, meaning if we hold two aces it is not correct to assume our opponent is aware there are two less aces in the deck. Additionally we may want to consider that sometimes an opponent's estimation of EHS' is inflated by in turn observing actions denoting weakness from other opponents (and ourselves).

To address these problems we have added a level of abstraction to the opponent modeling in the original design. All the opponent models, including a model of ourselves (in effect our opponents' model of us), are gathered and adjusted using the public information available (our hole cards, private information, are not considered public information). In the re-weighting step for a particular player, when EHS' is calculated, a field array (Section 7.3) is used which is composed from the weight arrays of all the opponents of that player. As a result, the second re-weighting in a round is performed within the context of the first.

Of course, when we compute hand values for our betting strategy, we use all available information and do not include all the subcases which use one or both of our hole cards. Since the weight arrays have been normalized with these subcases included, some additional minor error is introduced.


next up previous contents
Next: 7.3 Using the Model Up: 7.2 Learning Previous: 7.2.3 Post-Flop Re-Weighting   Contents
Denis Papp
1998-11-30