Is it ever desirable to put more money in the pot when your hand has less than 50% equity against an opponent's range, even when there is no fold equity?
Sklansky says no: "...it is clearly incorrect to put more money in the pot on a hand you know to be the underdog" ("The Theory of Poker," p. 102). (To be precise, Sklansky believes there are exceptions to this principle in seven-card stud and razz, but in this post I'll be talking about holdem.) Yet an interesting example in MOP ("The Mathematics of Poker") seems to say otherwise. Let me reproduce the example here (Example 7.2, p. 76).
Quote:
The game is pot limit holdem, but with a special rule that only pot-sized bets (or allin bets if the player has less than a pot remaining) may be made. We call this the rigid pot limit game; it is substantially simpler than the full pot limit game (where players may bet any amount between a minimum bet and the pot).
Player X has: AA
Player Y has: 87
The flop is: 962
(We'll ignore runner-runner full houses for the AA and runner-runner two pair for the 87s for the sake of discussion. Assume that on each street the 87 simply has 15 outs and either hits or does not.)
We can immediately calculate Y's equity if the cards are simply dealt out:
<Y> = 1-p(miss twice)
<Y> = 1-(30/45)(29/44)
<Y> = 56.06%
The pot contains $100. Player X is first to act. How should the play go for different stack sizes?
Summary of the book's analysis:
- When stacks are $50, X checks, Y bets all-in, X calls
- When stacks are $400, X checks, Y checks
- When stacks are $1300, X bets, Y calls
The last case is pertinent to the topic of this post (and slightly counterintuitive); X, despite being the underdog, bets and Y, despite being ahead, does not raise but instead just calls. These decisions maximize the EV of X and Y.
According to this example, the answer to my question at the beginning is yes. On the other hand, this is a special situation in which both players know each other's hands and betting is rigid pot limit – conditions which do not hold in any real poker game. Yet the situation is not so far removed from actual poker play that anything similar seems impossible (and in my question I changed the condition of knowing an opponent's hand to estimating his range – something we are actually capable of doing consistently).
(MOP also takes up an example (Example 7.3, p. 80) in which the situation is the same except that betting is pot limit (not rigid pot limit), and the stack size is $400. In this case, X maximizes his EV by betting $23.26; Y is made indifferent to calling or making a pot-sized raise. Apart from being able to see each other's cards, this type of situation actually exists in poker.)
What do you think?