Theory question - bluffing/calling a bet against certain range

    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      Hi guys,

      there is one piece of the poker theory puzzle which i seem to be lost at..

      Recently i read in one of the books a simple math calculation for bluff and calling frequencies - how often u must be ahead to profitably bluff/call. As much as i understand how to determine the % on the "left side" (how many % we HAVE TO BE ahead), i'm kind of lost at how to actualy get the % how many time we ARE actualy ahead. We can put the guy on a range in a spot, we know our hand, but how do you calculate it? I seem to be lost at this somehow.. if u can provide an example, that'd be so great!

      thank you

      freespirit
  • 11 replies
    • Meemawuk
      Meemawuk
      Bronze
      Joined: 27.05.2009 Posts: 758
      Obviously it's based on how a hand plays out from start to finish, but generally you work out all of the hands in his range that he will bet the river with, work out as a percentage of that how many you can beat, then calculate based on his bet size as a percentage of the pot, if you can call profitably. For example, you can beat half the hands in his range that he would bet on river, and he has bet 1/3 of the pot, this would be a good call in the long run.

      Thats the most simple way I can explain it so I hope it makes sense?

      Edit for clarification:
      In the example consider that you have Top 2-pair. Villan will bet any top pair hand, weaker 2-pair hands, a few combos of missed straight draws, any missed flush draw, a set, and 1 or 2 completed straights. Against his range you are often beating more than half of his potential holdings, and he has only bet 1/3 of the pot. You could be up against one of the hands that beats you this time, but more often than not, you will have the best hand so in the long run a call is profitable.

      Hope this helps.
    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      this part makes sense, thank you.. Basicaly, for example:

      board Kh 8h 7c 3d Jd

      i have Kc Tc

      i can assume from the way how the hand was played, what the approximate range of my opponent is and i can stove the equity and compare it to the profitable call % when i face a bet on the river - like to be ahead 25% or more when facing a 1/2 pot size , this seems clear now

      How about the bluff efficiency tho?
    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      just read your edit - good example, thank you.

      Still i'm a bit lost on the bluff part
    • Meemawuk
      Meemawuk
      Bronze
      Joined: 27.05.2009 Posts: 758
      Well, before making the call I consider the frequency or likelihood that he will actually bluff in this spot because he will value bet a strong hand 100% of the time, but might only bluff 2/3, half, 1/3 of the time depending on the player and often the pot size.

      I usually discount the number of potential bluff hands (in the same way that you would discount 'non-clean' outs when you hold a drawing hand) a player can hold based on any read/history/stats that would suggest the player will only bluff a certain percentage of the time, to get a closer indication of whether or not the call is profitable. Some players simply will not bet the river with a missed draw under any circumstances, and it's a mistake to ever call even though there are missed draws in their range.

      Even still, If a player will bet the missed draw 2/3 of the time. 2/3 of the hands you can beat as a ratio of the total number of hands he can bet the river with can still justify calling a modest sized value bet on the river.
    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      You probably got me wrong - as for the bluffing part :

      i am trying to determine the % of how many times he will fold his hand to my river bet - as example, i have 9s8s and i bust my draw on the river - in order for my bluff to be profitable on the river with a pot size bet, the opponent have to fold 50% or more hands. How do i get this %?
    • Meemawuk
      Meemawuk
      Bronze
      Joined: 27.05.2009 Posts: 758
      Simplified, you calculate your bet as a percentage of (the pot + your bet).

      Example1.
      Pot is $100, you pot size bluff the river. Calculating the percentage your bet has to be successful to break even: (100/(100+100)) x 100 = 50%

      Example2.
      Pot is £100, you half pot bet bluff the river. Calculating the percentage your bet has to be successful to break even: (50/(100+50)) x 100 = 33%

      I'm not sure this formula is actually written on here, or even if its correct, but I'm sure I've read it somewhere or maybe even adapted it from the "flop play" C-bet success rate calculations.
    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      i've got the formula from the Blueprint, it's correct. My problem is, how do i apply it to the game - in certain situation? I mean, how do i calculate approx. amount of the time the opponent will actualy fold given the approx. range i put him on?
    • Fongie
      Fongie
      Bronze
      Joined: 02.12.2006 Posts: 4,978
      That's the tough part. To do this, you need to first think about what his range is.

      When you know his range (or have an estimate), you need to know how to count combinations of hands.

      Then, you need to decide which hands in his range he will fold to your bluff.

      When you know this, you just divide combinations of hands he will fold by total combinations of his range.

      For an easy example, if you decide he has 50 combos in his range and he will fold 25 of them, he will fold 50% of his range.

      Now, for your bluff to be profitable you need to make sure that % of his range that he folds, is bigger than the amount needed for your bet to be profitable.
      For example, if you bet a size that needs 33% fold equity to be profitable, he needs to fold more than 33% of his range.

      I hope that's clear enough. Estimating fold equity can be pretty hard ;)
    • freespirit47
      freespirit47
      Bronze
      Joined: 04.11.2008 Posts: 354
      Thanks Fongie, that's exactly the kind of answer i was looking for!
      Also , thanks to you Meemawuk for your input, looks like i got the puzzle together finaly :)
    • Meemawuk
      Meemawuk
      Bronze
      Joined: 27.05.2009 Posts: 758
      The Interesting part about this post is that I've recently been reading "the poker blueprint" and it's helped me in terms of calculating combinations of certain hands within a range more accurately. I play a LOT of live cash game poker these days and physical reads/tells contibute hugely to river decisions. Very much more than they do online!

      Edit: also! Fongie is better at explaining things than I am hence his status!
    • MatejM47
      MatejM47
      Black
      Joined: 21.01.2010 Posts: 1,193
      Hey,

      I really recommend watching hasenbraten video Major Leaks on No-Limit $50 Shorthanded - Part 3. The last AQs hand he explains in detail on how to calculate equitys needed to make a bluff profitable.

      Here's the link:
      http://www.pokerstrategy.com/video/9893/