Looking through some threads in the tournament discussion section I find a trend of posts for spots which are actually calculable - namely pre-flop calls of all-in shoves, and decisions as to whether to 3bet shove ourselves. I'm just going to use one of these hands, chosen for its simplicity really as a good case study. Thanks to HardTilt for the hand!
Originally posted by HardTilt
Hey! I wonder what alternativs do I have? I am trying to not call all in preflop often. The player who shoves, I put him on a range of 77+ KJs+ ATs+ But almost something like KQ or AQ, I wasnt afraid of playing against a higher pocket pair. Do I want to be AI against his range? I am 34bb and vallian is about 19bb. losing a flip here would hurt my stack... anyways, Am I thinking close to right here? Is it an easy call/fold?Grabbed by Holdem Manager
NL Holdem $1,000(BB) Replayer
SB ($21,706)
BB ($18,944)
UTG ($18,890)
UTG+1 ($47,113)
UTG+2 ($34,258)
MP1 ($9,826)
Hero ($34,214)
BTN ($13,254)Dealt to Hero 9♥ 9♦
fold, fold, fold, fold, Hero raises to $2,000, fold, fold, BB raises to $18,844 (AI), Hero ??
Calling spots:
In this case we are facing an all-in and we have a simple pair of alternatives: call or fold. For this exact reason we should be able to solve this spot - all we need apart from the maths is the ability to put our opponent on a reasonable range. Ranging a villain is of course an imperfect science - but we can choose a reasonable range based on what info we have.
The Maths:
In this case Villain is 3bet shoving 18,844 chips, but since we have already put in 2,000, we have to call 16,844. The HH curiously does not mention antes, but as most games on Stars would have antes by this blind level I'm going to assume antes of 12.5%. In this case the money we stand to win totals 18,844 + blinds + antes + the bet I've already put in (2,000) = 18,844 + 500 (we don't add the BB since the player shoving is the BB) + 1,000 (125 ante x 8 players) + 2,000 = 22,344.
So we are risking 16,844 to win 22,344, roughly 2:3. Most replayers will give us our exact calling odds, but in case we aren't using one we can derive it easily. We want to know our break-even point, how often do we need to win this hand to break even on the call? Essentially we want to know what proportion our calling amount is of the whole ratio. So we simply divide 16,844 by the total of the two figures. 16,844 / (16,844+22,344) = 42.98%, call it 43%.
Edge
We don't want to make break even calls, as we're risking chips for no benefit. We want to have more than 43% equity. How much more will depend on the situation, principally on ICM considerations. Assuming minimal ICM (no bubble, no FT bubble type situations), we only have to consider the softness and structure of the tournament. If it's a really tough turbo full of regs, we should generally take any edge going, even a fraction of 1%. In a super soft tourney with a great structure, we may be able to pass up several %. Generally 2-3% will be plenty in most spots.
Ranging villain
Now we know our break even point and assuming we require an edge of 1-2% over break even, we just have to figure out our actual equity vs. villain's range. This will depend a lot on reads, and even if we're readless, on the assumptions we make about a random in this particular event and buy-in. In this hand villain is a random in a $0.25 tournament, so almost certainly a fish. Fish will tend not to 3bshove as much as they should, so I would put him on a tighter range than a regular. Still, Hero is in the CO and Villain in the BB, so he can still be reasonably wide.
Let's put him on this fairly conservative range:
This should give us a sort of worst case scenario for the calculation. Holdem Resources Calculator tells us that vs. this range 99 has 49.7% equity, more than enough to make a profitable call. We can also check what should be the weakest call we make against this range by fiddling around with the calculator. In this spot, if we desire an edge of say 1% over break even, it turns out we can call as wide as 77+, AJs+ AQo+. Versus many villains I think we could call off wider still, but this is a safe range vs. a fish who may not shove that often.
What this helps us avoid:
Courtesy of the great blog lifewithfacecards, this method of problem solving should allow us to be active enough facing 3bet shoves, without risking being a "donk trying to play LAG" ♦
Questions:
What do you think of the range we give villain here? What range do you think we should give to a good regular here? What range do we think different villain types might flat call here in the BB? How much edge do you generally require over break even to make a call, ICM aside?
Please feel free to post your own examples of this decision process. Of course, we can use modern software such as HRC to avoid having to do any manual calculations such as those above, but I find doing them from time to time greatly helps in game intutive decision making and the accuracy of our in game estimations.
Finally
In my next thread I'll post a guide to figuring out how wide we ourselves should 3bet shove in different spots. Once that's up I'll link each of these to the other, since they are a natural pair.
Until next time, good luck at the felt!
A
