In online poker, a major breakthrough in the understanding of theory and practice came with the introduction of the HUD and advanced statistics. No matter how you feel about these tools, good or bad, they have changed our concepts and behaviour in the game. If you play online, the HUD is essential. Let's take a look at the stats and analyse how they can be used to adapt to the opponent's game.
Of course, HUD and stats are not synonymous. Stats in poker are discrete, mathematical expressions of frequencies. The HUD is the most comprehensible representation of these statistics. Although stats were never explicitly available before the advent of the HUD, they have always existed. Without the HUD, statistics would be understood in a very obscure way, much affected by the fluctuations that arise from personalities.
Our brains are not designed to process precise data, so someone with frequencies of 7% and 11% may look exactly the same to our intuition, but they may represent completely different player ranges. In the absence of statistics, the only way we can rely on trying to understand other players' frequencies or ranges is our intuitive guesses (and a little information from showdowns). One of the reasons why stats are so valuable is that they allow us to get past the inexact natural mechanism and predict our opponents more accurately. Most players who use HUDs have learned that even if someone seems to be playing very aggressively or with a wide range, and the stats say they are not, then we trust the stats more than our intuition (as isolated but significant events tend to affect intuition more than they should). Statistics are to us like vision-correcting lenses in a poker game.
In live poker, the only way to gather information is through our intuition and observation. But then again, even in live poker there are statistics, they are just not as clearly available. It doesn't matter so much whether your understanding of statistics comes from the HUD or from your intuition about how aggressive a player is at the table, but adjustments based on statistics are inherently more efficient because of the structure of poker.
A little about adjustment schemes. An adjustment scheme is a coded system whereby a player will exploit'ins or react accordingly to certain stats.
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