Card ranges. Equity-1 vs Karlson-Sklansky.

    • terpesheva
      terpesheva
      Bronze
      Joined: 15.02.2009 Posts: 156
      Hello all!

      I've got a question about range ranking systems, in particular "Equity vs 1 random hand" vs Karlson-Sklansky system.

      Could someone please tell me which ranking system is it better to use?
      As far as I understand, Sklansky system is based on playability of hands, hence it should be used for any calculations apart from ORC where you really want to see the equity-vs-1.
      Am I right?

      Thank you!
  • 1 reply
    • pzhon
      pzhon
      Bronze
      Joined: 17.06.2010 Posts: 1,151
      I didn't notice this question earlier.

      The Sklansky-Karlson (or Sklansky-Chubukov) rankings are not based on playability. They are based on an artificial NL situation. If your choices are to flip your hand over and then go all-in, or fold, then how deep can the stacks be so that pushing is better than folding? This primarily focuses on how often your hand is behind, and how much equity it has against hands which are ahead. It overvalues hands like A4o which are very often ahead in two-card poker, even though those hands may be tough to play in practice. It undervalues very playable hands like 76s which are often behind. If you turn 76s face up, then someone with T3o would know ten high is ahead, so you would not steal the blinds very often with 76s. The trash hand J4o is ranked ahead of the suited connector 76s in the Sklansky-Chubukov rankings.

      Hot-and-cold equity against a random hand also doesn't take into account the playability of the hand, and again it ranks J4o ahead of 76s. In practice, it is more valuable to win with a big hand which can bet for value against a second-best hand than to win with a bluff-catcher. It is more valuable to be able to hit the flop hard. So, in practice, I would almost always play 76s long before I would play J4o, and so I find both ranking systems wanting.

      One alternative might be to rank hands by their equities against the top 30% of hands. Another is to rank hands by their equities against two or more random hands. (Pokerstove's default is to use equities against three random hands.) To beat multiple players, you usually need to make more than one low pair, which may mean you have made a hand you can bet for value. Both of these methods place 76s far ahead of J4o.