According to David Sklansky in his book “The Theory of Poker”, the correct way to play a hand is to play exactly the same way you would if you knew what your opponent’s two cards were.
Since we know that this is impossible, what we are going to try to do is try to imagine our opponent's hand – or rather, his range of hands, which is a group of possible hands, based on the type of player and his actions.
Imagine a range
You may have heard phrases like “I gave you a ten, so I called” or “I put you on a king, so I raised”.
This is not a correct way to think about your opponent's cards. Guessing with exact accuracy the two cards he holds is virtually impossible, so you should try to imagine the range of hands he plays.
The problem is that putting your opponent on a range is not as easy as it seems.
At the beginning of a hand, the information available is so small that it ends up leaving your opponent's range very wide.
As the game progresses, you can gather information and reduce the range, thus increasing accuracy.
Example – Online No-Limit Hold'em cash game with blinds $1/$2 and effective stacks of $200
Your opponent on the button plays a standard tight aggressive game (also known as TAG – a player who plays few hands with a lot of strength and aggression), with a status of 18/15 (number of hands/pre-flop raise ratio).
You have :Jh :Jc and raise to $7 from UTG (first position to speak).
Two players call and Villain also calls on the BTN.
Since two players entered before him, his range increases and becomes much wider than normal, especially considering that he has absolute position.
Now let's think about the range: we can exclude AA, KK, QQ and AK, because with these hands he would almost always raise pre-flop, even more so against multiple opponents.
So if you were a TAG player and you were in this situation, what kind of hands would you play?
The answer is simple: hands that play well post-flop in multi-handed pots.
Let's be clear that a range is never 100% precise, but we can achieve good accuracy by analyzing the situations well. In this case, we can imagine the following hands for the player: AJ, Axs, KQs, KQo, KJs, 56s to QJs, 97s to J9s, 22 to TT.
This range is quite wide as you can see, and to reduce it we have to wait for the flop and observe their actions.
The flop
The flop comes :6s :7s :2h. You bet $25 and both limpers fold, while the button calls.
Your opponent called preflop after two limpers and has now called your bet on the flop as well. You can take several hands out of your range after this action.
First, you can eliminate overcards (two cards higher than the board, e.g. KQo). A TAG opponent would fold overcards to a bet when he misses the flop.
If he had an overpair like 88 or 99 he would probably raise the flop, so we can discount those hands as well.
What we were left with were draws, sets, two pairs and weak hands like one pair.
Our villain's post-flop range has been reduced to something like: 89s to KQs, 67s, 89, 78, 79, 77, 66, 55, 22.
With all of these hands, our villain TAG would probably call at least on the flop. Of course, in some hands our villain would raise, but since we are trying to create a range, it is better to put all possible types of hands that would continue after the flop.
As you can see, we have eliminated a good part of our villain's hands, now we have an idea of what our opponent might have.
The turn
The turn brings a :Ts. You bet $50 and your opponent raises and goes all-in. Do you call?
Let's think about our opponent's range. What hands would call preflop, call flop, and raise all-in on the turn?
Based on the range of hands we have from our opponent, we are completely beaten in this hand. He would rarely follow this line of action with worse hands than we imagine in his range.
Everything becomes clearer when we have information
What starts out as a blurry vision in the fog becomes clearer and more obvious as we place our opponent in a range and make decisions based on data and information.
Remember, the idea of a range is to put your opponent on a range of hands, not an exact hand. The idea is simple: eliminate what he probably doesn't have and guess what's left.
Understanding the concept of range and analyzing it is one of the most important tools for improving your poker game.
If you can accurately deduce your opponent's range, you will make fewer mistakes, and consequently win more.
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interesting….
Thank you!
What books do you recommend to improve this aspect of my game? I have been playing poker for a short time, I identify with the game a lot and I find it quite easy to assimilate concepts. I thank you in advance.
Vitor, there are Harrington's books that I think are very good. I know that there are many people who say that the information in books is outdated and I have to agree in a way, but they contain a lot of valuable information. After all, there is no today without the existence of yesterday. And yes, in my opinion, you can learn a lot from books, especially because many of those who talk about them don't understand that each person assimilates information in a different way. If you have any questions, send me an email and we can discuss the subject. [email protected]
I really liked the article. Especially online, it is difficult to analyze your opponent, being able to form range ideas is a good strategy. If you can, I would like to read more articles on the subject. Thank you.