Someone who follows the Polished Poker (free poker books) thread on cardschat posted up a hand that I think illustrates the primary opinion gap divide among good poker players. That is, how often will someone do X? Online, all you have to go off of is some stats, and maybe some patterns on how someone plays certain situations more consistently (if you’re lucky and they have an exploitative pattern). Most of the time you’re operating on very limited information that you’ll need to translate quickly in order to make +EV (expected value) decisions.

The EV of a call, fold or raise of a situation typically comes down to two things. What kinds of hands does this opponent have in his range considering how he played it and the board. And how often does he do Y play with each of these hand groupings. Now, usually most good players don’t have much of a difference about what an opponents hand range will be. Most of the time they’ll both be dead on here. The great divide occurs on how often are they doing X in Y situation, or in poker terms, how do we wight their hand range? Here’s a great example that I think illustrates that issue perfectly. This hand was just posted yesterday:

 

(Full Tilt) $10.00 USD NL Texas Hold’em – Sunday, September 21, 04:39:21 ET 2014 Table Highwood (Real Money)
Seat 3 is the button
Seat 1: Player1 ( $5.16 USD ) – VPIP: 15, PFR: 6, 3B: 0, AF: 4.5, Hands: 89
Seat 2: Hero ( $19.83 USD ) – VPIP: 14, PFR: 9, 3B: 4, AG% 27, Hands: 142
Seat 3: Player3 ( $11.44 USD ) – VPIP: 16, PFR: 11, 3B: 3, AF: 3.3, Hands: 371
Seat 4: Player4 ( $19.49 USD ) – VPIP: 27, PFR: 12, 3B: 0, AF: 2.7, Hands: 116
Seat 5: Player5 ( $11.05 USD ) – VPIP: 12, PFR: 6, 3B: 4, AF: 1.7, Hands: 361
Seat 6: Player6 ( $11.32 USD ) – VPIP: 9, PFR: 7, 3B: 1, AF: 4.0, Hands: 381
Seat 7: Player7 ( $12.24 USD ) – VPIP: 20, PFR: 15, 3B: 4, AF: 2.3, Hands: 137
Seat 9: Player9 ( $10.08 USD ) – VPIP: 27, PFR: 9, 3B: 9, AF: 2.0, Hands: 283
Player4 posts small blind [$0.05 USD].
Player5 posts big blind [$0.10 USD].
** Dealing down cards **
Dealt to Hero [ Ks Ac ]
Player6 raises [$0.40 USD] Villain has EP vpip 7%
Player7 folds
Player9 folds
Player1 folds
Hero calls [$0.40 USD] 3 bet here looks mega strong, prefer to call.
Player3 folds
Player4 folds
Player5 folds
** Dealing Flop ** [ 5d, Kh, 8h ]
Player6 bets [$0.50 USD]
Hero calls [$0.50 USD]
** Dealing Turn ** [ 2c ]
Player6 checks
Hero bets [$1.36 USD]
Player6 calls [$1.36 USD]
** Dealing River ** [ 3d ]
Player6 checks
Hero bets [$1.15 USD] going for that extra bit of value from QQ JJ but I thought he probably has the same as me, AK as played.
Player6 raises [$5.00 USD] OK now I wish id checked behind

So here, hero is facing an obviously tight opponent in a full ring cash game. The opponent is very tight pre-flop(7% opening range), but pretty aggressive postflop (4 AF). They are opening UTG, but we’re told, in a small sample size, that the opponent has been opening 7% from UTG. That stat probably isn’t normalized, and is likely a little tighter. But regardless, this is a good example because the beginning range is small, so it makes deduction of range that much easier. The wider someone’s range is of course, the more difficult that becomes.

Hero doesn’t 3-bet pre-flop because he thinks it will look too strong and fold out most of his tight opponents weaker range. And he’s probably correct here, so he just calls. Hero flops top pair with top kicker on he flop, and faces a 1/2 pot bet and just calls. The turn is about as much of a brick as you’ll get, and hero’s opponent checks, hero bets, and his opponent calls. The river is another complete brick and his opponent checks again. Hero thinks he’s good here, and most of the time he will be so he goes for value, but bets pretty small and then gets check raised. So now hero is stuck trying to decide if he got played. His opponent is tight and will usually have a very strong range here. Hero is getting 2.5:1 on a call, so he only needs to be good 28% of the time.

Most poker players when analyzing this hand will say hero’s opponent will have a range of: AA-KK, AK, 88, and at least one or two bluffs like AhQh and AhJh. I think it’s fair to put both of those in the opponents range because those would both be in the top 6% of hands being raised UTG from a tight player. The divide is going to be on how often the opponent will bluff with these two hands? If we say he will always bluff with these two hands, especially considering the small value bet on the river by hero, which will open up his opponents bluffing range a bit, then the check-raise becomes a call because hero only needs 28% to call, and he’s be getting 33%.

Ace Poker Drills – Poker Equity Calculator
Board: Kh 8h 5d 2c 3d

Equity            Win               Tie               Hand Range
66.6667%          46.6667%          20%               [ KK+(100), AKs(100), AKo(100), AhQh(100), AhJh(100), 88(100) ]
33.3333%          13.3333%          20%               [ AcKs ]

BUT…. if we say that hero’s opponent is almost never check-raise bluffing here, and reduce those two hands to 10% of his weighted range, then the check-raise becomes a fold because hero will only be getting 24.2% on a call.

Ace Poker Drills – Poker Equity Calculator
Board: Kh 8h 5d 2c 3d

Equity            Win               Tie               Hand Range
75.7576%          53.0303%          22.7273%          [ KK+(100), AKs(100), AKo(100), 88(100),AhQh(10), AhJh(10) ]
24.2424%          1.5152%           22.7273%          [ AcKs ]

So the big question is, how do you fill that chasm so you can adequately come up with good post flop analysis that will be helpful to your poker game long term? There’s really no perfect answer here because you’re dealing with incomplete information, so you’re answer won’t, and can’t be complete (or perfect). However, there are some general guides you can use to weight hands better. Some of this is common sense, but it’s important to note:

  1. The tighter a player is, the less likely they are to bluff. So bluffing hand ranges and their weights should be reduced a lot.
  2. The more aggressive an opponent is, the more likely they are to bluff. So those ranges bluffing ranges and their weights need to widen and weights increase.
  3. Not many players check-raise bluff the river, thus the tighter this reduces their bluffing range even more.
  4. On decent samples, if W$WSF is high (over 46%), then you’ll need to increase bluffing ranges and their weight a significant amount.
  5. Weak bet sizing can induce or widen any opponents bluffing range, so weight needs to increase.

You take all of this information and you try and come up with a number. In this specific case, you have a tight opponent, but they are fairly aggressive post flop. They aren’t just check/calling their way down. You have some offsetting characteristics here. #3 above reduces the bluffing range, but #5 above offsets it a bit because hero’s bet sizing was pretty small. There’s no data on #4. So in this case, you’re somewhere in the middle, but probably slightly under 50%. The bluffing range is already tight. There’s only 2 bluff hands in there. The weight of those should probably be set somewhere under 50%, so I’d set it at 40% in this case. If we look at those numbers now:

Ace Poker Drills – Poker Equity Calculator
Board: Kh 8h 5d 2c 3d

Equity            Win               Tie               Hand Range
72.4638%          50.7246%          21.7391%          [ KK+(100), AKs(100), AKo(100), 88(100),AhQh(40), AhJh(40) ]
27.5362%          5.7971%           21.7391%          [ AcKs ]

Wow… just under the required 28%. About as close as you’re going to get (less than 0.5%). The good news in these situations is that call or fold become pretty indifferent. If you folded in this spot, you didn’t really lose much, and the same with a call. So the EV is pretty neutral. The bad news is that the weighting controversy will go on ad nauseum. lol But I hope this provides some insight into how to think through the weighting of hands, and the difference that it makes.

Oh, and an easy way to use an equity calculator and weight ranges is the ace poker drills equity calculator. If you don’t use it, check it out. It’s worth taking a peek because it makes this process that much easier:

Poker Equity Calculator