Exploitative play is the practice of taking advantage of an opponent's weaknesses in a game. Since, for example in poker, most players do not use Nash equilibrium strategies, the most profitable counter-play is typically also not a Nash equilibrium strategy. As a consequence the most profitable players (human or AI) will be ones that efficiently take advantage of the other players' weaknesses. In fact, the usual notion of poker is that there are fishes (who play weakly) and sharks (who play exploitative).
Another familiar example of exploitative play is the use of tells in poker.
All exploitative play requires some opponent modeling in order to understand the weaknesses that can be exploited. This can range from simple rules-based notions to very sophisticated opponent models. Pokerbots that use exploitative play as a strategy are called exploiters.
Player Types and How to Exploit Them
The following player types apply to no-limit holdem 6-max or full ring. It is usual to identify player types based upon Player statistics. The most important are: VPIP and PFR, though AF is also useful.
VPIP: 12-16, PFR: 9-14, AF: >2.0
Description: The tight aggressive player is a very common type of regular player who simply waits for premium hands. They select their pre-flop card well, have some knowledge of position and are able to basically read cards. When they choose to play a hand, they generally play aggressively.
Exploit: Generally difficult to exploit without some other apparent weakness. Easier money elsewhere. TAGs will often play quite predictably and a good LAG can take advantage of them.
VPIP: 7-11, PFR: 5-7
Description: Plays very few hands and only premium ones at that. A nit who flat calls a raise probably holds a a pair and is looking to set-mine. A nit who re-raises generally holds QQ+,AK. They generally do not play suited cards (except AQs+) so straights and flushes are less likely.
Exploit: Steal their blinds. C-bet relentlessly if they flat call your pre-flop raise. If they offer any resistance then they either hold larger over-pairs or trips. Any nit looking to get a lot of money in the pot usually holds trips. If a nit has called a pre-flop raise then they will usually fold to a squeeze, especially if the raise makes the Stack-to-Pot-Ratio (SPR) unprofitable for set-mining.
VPIP: 17-24, PFR: 15-22, AF: 2.0-5.0
Description: Plays a wider range of hands than a TAG and also plays aggressively. Uses position to their advantage and will raise and re-raise more often. LAG players have good hand-reading skills because a large part of their profit comes from getting others to fold better hands. This uses a concept known as fold equity.
Exploit: Easier just to avoid them. Either be a more skillful LAG (variance). Be prepared to call them down lighter. Three bet more often when in position. Post-flop strategy is to either Hammer with a large re-raise or to call them down to the rive then re-raise the river (Rope-a-dope).
VPIP: 30-100, PFR: 30-60, AF >4.0
Description: The crazy gambler type who likes to get their chips in the middle. They will virtually never call - they bet, raise or occasionally fold. They will occasionally look at the strength of their own hand, but never understand the strength of your hand.
Exploit: Either play only premium hands up and wait for them to bust off the table, or flat-call them in position and then call them down with any kind of holding top-pair or better. Prepare for some variance, but in the long run you can make a lot of money from them.
VPIP: 18-100, PFR: 0-15, AF: <2.0
Description: Never folds and hardly ever raises. If they raise they are generally holding a very very strong hand. They will call down bets with any kind of holding, including weak draws.
Exploit: Play Fit or fold poker - bet when you have a hand, check/fold when you do not have a hand. You can control the size of the pot here by betting smaller when your hand is weak and larger when your hand is strong. If the board is wet then punish the calling station by betting larger if you think they are drawing. You can adjust your pre-flop range vs them depending on their VPIP - the larger their VPIP, the wider your pre-flop range can be. Calling stations can be very profitable fish.
VPIP: 5-9, PFR: 4-9
Description: They have a 20BB stack and are either all-in or fold by the flop. They are generally playing only TT+,AK. They will generally never have an SPR that makes set-mining smaller pairs profitable and are generally looking to play on the strength of their hole cards alone. Given their small stack sizes and generally tight image, they can often profitably squeeze from late position and steal blinds more often.
A person who has a small 20BB stack but has higher VPIP/PFR is probably a fish.
Exploit: Luckily short stackers play so few hands you can generally avoid them. Stay away from tables with more than 2 short-stackers.
Loose Fish/Loose Passive
VPIP: >30, PFR <15, AF <2.0
Description: Opens with a lot of hands and plays passively post-flop.
Exploit: This is your favourite kind of fish. Raise to isolate - you can do this with a wider range of hands than usual. Post-flop play depends on how the Fish plays: if they are a calling station, then play post-flop as if they are a calling station above. If they fold a lot then play aggressively even with nothing. If you have a reasonable holding then try extract value through slow-play.
See a flop, fit or fold
VPIP: 15+, PFR: ?, AF: <2.0
FCB: <35%, FvFCB: >60%
Description: They rarely c-bet so they have a low Flop-Continuation-Bet (FCB). Their Fold-vs-Flop-Continuation-Bet (FvFCB) statistic is greater than 60%. Once they enter a pot pre-flop they will call anything just to see the flop. Once they see a flop, they will check/fold if the flop misses them.
Exploit: Raise to isolate when in position. C-bet relentlessly with any two cards - they will fold often enough to be profitable for you. Check/fold to any resistance from them unless you have a reasonable holding.
- Common Poker Opponents
- Opponent Profiling