Probability of facing as steal while in BB

    • Johnis
      Johnis
      Bronze
      Joined: 23.07.2009 Posts: 77
      Hey guys,

      I was trying to calculate the probability of facing a steal (openraise from CO,BU,SB). I am a bit confused.


      Should the formula look like this ?

      P(co)*(1-P(bu))*(1-P(sb) + P(bu)*(1-P(co))*(1-P(sb)) + P(sb)*(1-P(co))*(1-P(sb))


      Any ideas ?
  • 5 replies
    • Johnis
      Johnis
      Bronze
      Joined: 23.07.2009 Posts: 77
      The alternative and more logical formula for me would be:

      P(co) + P(bu)*(1-P(co)) + P(sb)*(1-P(co))*(1-P(bu))

      That's because if cutoff steals, the further players don't have a chance to steal as well, so we shouldn't take them into account, if you know what I mean.

      Basically I got confused between these two, since I assumed the following ranges, and get 0.8862 possibility that I will be facing a steal in BB, which looks rather high:

      CO-30%
      BU-75%
      SB-35%
    • mbml
      mbml
      Black
      Joined: 27.11.2008 Posts: 20,698
      your formula is more complex, not going to check if it's correct.

      the easier way to do it is...

      Probability of Not Facing a Steal = 0.7 X 0.25 X 0.65
      Probability of Facing a steal = 1-P(no steal)
    • VorpalF2F
      VorpalF2F
      Super Moderator
      Super Moderator
      Joined: 02.09.2010 Posts: 9,418
      Both methods give the same answer.

      However, I don't think I understand the value of merging these players together.

      If button is open-raising 75% of the time, your reaction to an open-raise from him would be quite different than your reaction to an open-raise from the SB

      In the first case, vs the BTN you are OOP if you call or 3Bet but likely face a weaker hand.

      vs the SB, you will always be IP, but face a stronger hand.

      Another way to look at this is that 12% of the time you get a walk in the BB.
      *That* seems high to me.

      Of course, that is also the % of time you get
      66+,A9s+,KJs+,QJs,ATo+,KJo+

      Coincidence?

      Maybe...
      --VS
    • Ramble
      Ramble
      Bronze
      Joined: 17.11.2008 Posts: 1,460
      Originally posted by VorpalF2F
      Another way to look at this is that 12% of the time you get a walk in the BB.
      *That* seems high to me.

      Of course, that is also the % of time you get
      66+,A9s+,KJs+,QJs,ATo+,KJo+

      Coincidence?
      Hahaha - good one!!!
    • Johnis
      Johnis
      Bronze
      Joined: 23.07.2009 Posts: 77
      Since I didn't get replies for a while, I forgot about this question. Thanks Galvin for the reply, the formula is definitely easier, I forgot about the opportunity to count the probability of the opposite event :D

      Vorpal - I don't really remember what I was doing, but it was not about defense vs steals for sure. It was more about what is the impact if I do not defend enough, how much lower my potential "ideal" winrate is.

      I am underdefending OOP, but I am having a hard time playing OOP, without initiative, with a shitty hand... Don't know what boards to bluff postflop basically :) It is kind of easy to say check-call TP and some strong draws and Check-raise bluff backdoor stuff, and barrel scare cards. I usually play zoom, and underdefending is really bad in there, however the player pools are huge... So you very often don't have reads and have to bluff.

      I am certainly aware that i have to open up my range (i think overall i fold to steal 65-70, which is too much), but by this formula I kind of wanted to know how much the opponents would be "autoprofiting", by me folding too much :)

      Regards,
      Johnis