Monday, January 26, 2009

Session length and profitability

Q: How long do you think on average you have to put in at a table to increase the likelihood that you have a profitable session? I mean obviously in hold’em you can double your money at any time, but from a reasonable statistical odds perspective, how long does it take for a double up hand or several moderately profitable hands to come along?

Brendan in California

A: Assuming you are a consistent winner in a given poker game, your chances of posting a profit in any individual session definitely increase the longer you sit in the game, up to a certain point of diminishing returns which varies based on your own stamina and game conditions that are not under your control.

Your likelihood of posting a winning session increases as time passes for two main reasons. First, you are acquiring information about your opponents every hand they play. You might observe tells, see their cards at showdown, or see cards that they voluntarily show. As time passes you will be able to roughly categorize them as a certain player type and have a better sense of their possible range of hands following a given betting sequence. The second reason that a winning player figures to be ahead after a longer session is that over time, a player's actual results will more and more closely resemble the statistical expectation of his plays. To illustrate this, imagine the scenario where an expert player and a rank amateur both get all in before the flop with stacks 500 BBs deep. The expert holds AA and the amateur 33. The expert's aces are an 82% favorite to win the pot, but at the conclusion of this hand the expert won't have 82% of the chips in the pot, he will have either 100% or 0%. So, in the short term, neither result (win 100% of pot or 0% of pot) will accurately reflect the long-term statistical expectation of this play. Over time though, the player's results will more and more closely approach the expectation of the plays he makes, therefore, for a winning player, the likelihood of booking a win increases over time (provided his edge over his opponents remains constant).

Of course in the real world, one's skill advantage is NOT a constant. To use poker author Tommy Angelo's term, we are capable of playing not just our "A games" but also slipping into our "B games" or "C games", sometimes without noticing that we've done so. Players tilt, or begin playing something less than their "A game", for any of a number of reasons. Even for someone considered relatively untiltable (some have said this about great cash game players like Phil Ivey or the late Chip Reese), there is a limit to the brain's ability to function at a high enough level to continue to beat the game. So even if you are not prone to tilt as a result of outside influences, all poker players reach a point of diminishing returns when exhaustion saps them of their normal edge over the opposition.

Your edge over the table can also dry up for two other reasons. As a no limit cash game player, I've noticed that over the course of a session (and also over longer periods of time, by extension), the money in play tends to become more and more concentrated in the hands of the better players, where it is harder for you to win. Most poor players will lose their money to the better players, and those who do manage to win in the short term will (unfortunately for us) sometimes realize that they got lucky (or that they are uncomfortable playing a big stack) and cash out. An advantage player is thus going to earn the most during the "sweet spot" of any playing interval, before the fools and their money have been parted. In a standard daily cash game, this might mean that you are well into your session by 7 pm and will be fully alert until the last call for drinks at 2 am. Applying this concept over a longer time interval, it's been noted that at the World Series of Poker each summer, you might fare best during the first few weeks, when the money in the poker economy is still spread around in everyone's pockets, before many players have gone broke and a select few have had big scores in the tournaments.

The second reason your edge can dry up is that if you're playing against opponents who are at all observant, they will begin to form some ideas about your play just as you've been studying theirs. Perhaps your play falls into certain patterns, such as re-raising pre-flop with only AA and KK, or never raising on the river as a bluff. While these are somewhat problematic patterns to fall into, in the short term they will rarely hurt you too badly. But in the long term, against observant opponents who have been studying you, you will be giving them information that is too perfect and falling into patterns of play that are highly exploitable. This was an extreme example, but the point remains that almost all poker players have patterns that we fall into, and our edge over our observant opponents lessens over time as they make sense of these patterns. This is why it is particularly important, when playing against foes who you expect to face many times in the future, to mix up your play and create blended hand ranges. Otherwise, if you've raised UTG and you only do this with big pairs and high cards, your opponents will have a field day with you when they call you in position and catch a ragged flop like 7 6 3.

So, we've established that a winning player's chances of booking a win increase over time, but something else to keep in mind is that even the most skillful players in the world have losing sessions regularly. Even in no limit games, where the expert wields the additional weapon of sizing his bets precisely, and can thus expect a higher percentage of winning sessions that an expert limit player, the losing sessions still occur. In his book, Ace on the River (see p. 30), Barry Greenstein notes that for a given period he booked a win in about 58% of his limit hold'em sessions and over 75% of his no-limit sessions. So, even if you are Barry Greenstein, you cannot approach an individual session with the mindset that you can reasonably expect to be ahead after X hours. Instead, you approach it knowing that if you are a favorite in the game, you KNOW you will be ahead in the long term, and that playing 8 or 10 or 12 hours today, and tomorrow, and so forth, is how we reach that long term.

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