The majority of betting decisions are made based on a variable which
represents the strength of Loki's hand in the current situation.
Basic hand strength (HS_{n}) is
the probability that it presently has the strongest hand.
This alone is not fully adequate when there are more cards to come
which can easily change the situation.
For this reason, we compute the potentials PPOT and NPOT,
which tell us Loki's probability of winning/losing given that it is currently
behind/ahead.
Using these values we can compute an estimate of Loki's chances of winning
at the showdown (or of being the strongest after the next card, if it is
the flop and we are using PPOT_{1}). We define effective hand strength
as
EHS = HS_{n} + (1-HS_{n})*PPOT - HS_{n}*NPOT. | (6.3) |
However, there are some problems with including NPOT in the
calculation. First, when we bet we do not know if our opponent
will play. Second, in many situations where we compute a high
NPOT, it is often a better strategy to bet/raise to force
the opponent out of the hand. So when effective hand strength is
used as a betting decision (as opposed to a calling decision) it is
preferable to use a more optimistic version, EHS':
The basic betting decision used in Loki is similar to Figure 6.2, with the exception that EHS' is used instead of HS_{n}. A Make2 hand is defined as a hand with . We raise when less than 2 bets have been made this round, otherwise we call. A Make1 hand is defined as a hand with . We bet if no one else has, and call otherwise, except when it is 2 bets to call and we have not already called a bet this round. Finally, with EHS' < 0.50 we consider the strategies of semi-bluffing, pot odds and showdown odds (instead of resorting to Make0 as in Figure 6.2). These thresholds are an ad hoc but reasonable way to decide when to bet based on strength.
The lack of the ability to raise beyond two bets after the flop is a historical artifact, although not likely to be very limiting. Of course it must be addressed eventually, but it is a low priority function and hopefully will be superseded by a more general betting strategy.