If you are looking to improve as a poker player one crucial and compulsory step of your progression will be to stop trying to put your opponents on one single hand, and to start thinking in terms of a range.
What is a hand range?
Hand ranges are a grouping of feasible hands that you assign to your opponent as the action unfolds during a hand.
Let's begin by analysing a scenario in which a good player, who seems quite tight, opens to 4X the big blind, under the gun. You call in the small blind with 7,7. The board rolls out 8c,4d,2s, with a 4s on the turn, and a 5d on the river. Our opponent bets flop, turn, and river. If you choose to call your opponent down through all streets, before watching him flip over K,K and saying to yourself “I thought he had A,K” – you haven't formulated a range for your opponent, and are making a few errors in your thinking.
It isn't necessarily a mistake to put A,K into your opponents range at a certain point in the hand, but you have to ensure that your mind remains open to multiple possibilities when it comes to defining their hand. Your opponent can have many overpair to the board type of hands, and perhaps a pocket pair that flops a set. Don't put your opponent on a single hand while refusing to let the action guide your read. When thinking about a range of hands, it's important to know that your information starts out very incomplete, and the range is wide. The developing board guides you through a progressive process of narrowing that range.
In blue: A (very) tight Preflop Range
1) How do we determine our opponent's range?
– Start preflop, and progressively narrow the potential holdings of your opponent.
Preflop betting factors should begin the procedure of formulating and narrowing the range of potential opposing hands you could be facing. If you exclude a possible hand from your opponents range, never include it again on a later street. Ranges should always be narrowing or remaining constant, never expanding. In our example, a 4 in our opponents hand would give them one of the best hands available, but should effectively be excluded from their range because, how many tight players open with K,4 or A,4 under the gun? None. If they are not holding a hand preflop, then they cannot have it on the river!
What you should do: Don't try to guess the hand of your opponent preflop. Assign them a group of hands and gradually narrow it, by removing the holdings that they wouldn't have played in this way.
– Understand the logic of your opponents
Nobody is making random decisions at the poker table. The range of your opponent is always built upon foundations of logic! You must decipher the thinking process behind their actions! Good players will for example, be aware of position, stack depth, and which players are in the pot. They might 3 bet a button simply because a weak player opens the betting. The 3 bettor is isolating the weak player, and has a very wide range here.
Bad players also have their own logic and are far from being "unpredictable." Stop saying "he plays everything, so he can have everything” and you will find out that very often, they have a distinguishable way of playing in certain given situations.
What you should do: Understand that each player has their own way of thinking, and find the logic behind their ranges
– Betting patterns
You should be able to spot reliable betting patterns against some of the players that you face. It’s the first information available on the table and It’s the most reliable information available. Memorise how your opponent is betting in a given situation. Assume that he is very likely to follow the same thought process in a similar situation in the future. Start to be build your thinking process on this information and don't over think the value of physical tells. Players are habitual, and their actions can help you to drastically narrow their range.
Preflop questions should include: How many hands your opponent is raising, and whether they bet bigger with strength. Perhaps they even limp marginal hands?
Postflop questions should include: How often does your opponent slow play big hands, how do they play draws, and can they be pushed of mediocre hands easily? Do they fire at the flop, then give up when they have nothing?
What you should do: Use your memory and your sense of observation to spot reliable betting patterns
2) In Practice
Preflop : You are holding 77
In the example we looked at earlier, your opponent raises to 4 times the big blind. We should immediately ask ourselves if this is an unusual sizing. Also, almost every player will be opening a tighter range of hands under the gun compared to near the button. For a tight player, his opening range could be as narrow as JJ-AA and AK.
His range AA, KK, QQ, JJ, AK
Against a tight opening range, it is very likely that your opponent will fire at least one barrel with all of their range, including making a continuation bet A,K. With their range being so heavily weighted towards bigger pairs, you can easily take this opportunity to fold the flop in our scenario. Be flexible though, and look for anything unusual in their bet sizing that could change your mind.
His range AA, KK, QQ, JJ, AK
Turn: 824 – 4
If your opponent bets again on the turn, it's always worthwhile considering whether they have a tendency to bluff a lot, or to struggle with giving up the pot when holding AK.
His range: AA, KK, QQ, JJ, Sometimes AK.
River: 8244 – 5
Many tight players are prone to betting two streets, but most of them are only ever shoving rivers when they have the goods. Unless you have already seen your opponent making massive bluffs, it's unlikely at this stage, that he is holding less than an overpair
His range: AA, KK, QQ, JJ, Almost never AK
Considering the full thinking process, it is now obvious that calling your opponent down on the river with 77, is more than incorrect.
The range of your opponent river: Don't put him on AK!
– Never be tempted to put your opponent on a single hand. Think about groups of hands that make sense.
– Refine your judgements about range through each betting street. Use a process of elimination.
– Think about which stories make sense, and which don't. Base your judgements on facts and your own knowledge.
Article by Craig B.