Saturday, August 11, 2007

Equity of that K5

I thought I'd look at that button call with the K5s and 6 callers in front of you (with on raise) in some more detail.

Using pokerstove, if the raiser is raising with the top 20% of his hands and the other callers are playing the top 60% of their hands then the K5s has equity of about 13.5%, the callers 13.6% and the raiser 18.5%.

To make a call worthwhile based on pot equity alone the hero would need about 14.3%. But with the added value of the button, at that point you're actually in think about raise territory.

If the kicker was a little better, say a K8s, the hero's equity is about 13.9, the other callers 13.5. Still in the call territory.

What about A5s? It's worth a raise just based on equity. Against that 60%/20% lineup the A5s has 16% equity, the callers 13.2% and the raiser 17.8%. This is an example of a situation where you don't have to think you have the best hand for it to be worth a raise on value alone, you don't need to try to reduce the field to make it worth a raise, in fact you don't want to reduce the field.

How about pair? That's a hand Mason said he'd call with. A 66 is worth a raise here. It's in even better shape (just slighly) than the A5s.

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Friday, August 10, 2007

Implied odds with a flush draw in a loose game

Jumping ahead in the discussion about that 2+2 thread about me, a commenter towards the end of the thread says
I believe the references to his book were minor in nature and probably nothing Ed Miller/David didn't know already. Just stuff that was in his book before Ed published his.



That's a perfect example of how people deal with cognitive dissonance. Cognitive dissonance is when the observed reality doesn't match with your beliefs, in particular when people find themselfs doing things that dont' match with their beleifs.

The dissonance we have here stems from the beleif that 2+2 books are always "correct", a claim that Mason has made over and over since before 2+2 actually published its first book. Miller was still dressing for his prom when my book was being written, so the relevant 2+2 players are the other two authors of Miller's book, David and Mason. Did my book contian anything they didn't know already?

The true beleiver has to claim they did, otherwise there would be dissonance stemming from his beleive in infallibility (is it starting to sound like a religious cult?).

There are a few psycholocial tricks people use to fool themselves into dealing with dissonance. A primary method is simply avoidance of exposure to ideas that cause dissonance. That's the primary function of the heavy handed moderation at work at 2+2 forums.

Anyway, the tactic in my book that was the primary motivation for me writing the book was the idea of value betting a flush draw on the flop. I had made the observation when playing in some double bet on the end limit hold'em games in Victoria, Texas and Lake Charles, Louisiana. When I realized that the idea was also true in loose games that didn't have a double bet on the river I went to the internet to look for some reassuaance about my thoughts. (another way people tend to cope with cognitive dissoanance).

Prior to that most of what I thought about limit hold'em came from reading others, mostly Sklansky. The general beleive, preached by David, was that there were a lot of reasons to raise a flush draw on the flop, but they centered around semi-bluffs and free-card plays, not value. I thought that popular wisdom was wrong and that there were situations where draws could be bet for value.

I knew this was the case in some cases in draw because I'd done a game theory related paper on the subject for a conference in operations research (applied math) when I was a graduate student. But since it required multi-way action in hold'em the mathematics wasn't so straight-forward and I wanted to talk about it.

I posted something about it to rec.gambling.poker. That post got zero responses. So I posted something about it to twoplustwo.com. Although I'd played IRC poker on the internet before that, I'd never posted to one of the forums before.

Mason responded basically telling me that I was an idiot and that since he had never heard of me it couldn't be possible that I knew what I was talking about.

From that a book was born.

I eventuall found a half-dozen people on rgp with similar thoughts and after refining my thinking in dicussions with them, managed to turn the idea into a book.

What did Mason think about playing draws for value before my book was published? It hadn't occured to him. The idea that he already was familiar with the idea is laughable.

In a thread from 1998, Bob Morgan posed the question


20/40 HE - loose game, six callers in front with one raise. I know the pot is going to have at least six-way action. I'm on the button witk K5s. Should I call or fold?


For those who have read my book you'll realize that not only should you call, if the hand was just slightly better (like K6s) you should probably raise. Mason made a comment in that thread that shows his ignorance of the idea of raising flush draws for value.



Re: The semi-pros are 50-50 on this one!
Posted by: MasonMalmuth@TwoPlusTwo.com (MasonMalmuth@TwoPlusTwo.com)
Posted on: Saturday, 7 February 1998, at 3:08 a.m.

I almost always throw this hand away. The problem with calling is that your implied odds are not as good as they seem. In a typical $20-$40 hold 'em game you will have to pay to make a flush assuming that two of your suit come. On the other hand I would play any pair in this spot.



With at least 7 people seeing a flop for two bets it's not going to be a stretch to think that you'll get 3 callers on a flop bet if you flop a flush draw. In that case Mason is just wrong to think you'll have to pay to draw to the flush. You'll profit from just drawing to the flush (in terms of EV).

The whole idea of a draw being better than a "made hand" is one that Mason just couldn't process. He's since figured it out (I think) but he fought the idea very hard for a long time.

David also didn't understand the concept at the time, but he did more quickly understand it once it was pointed out to him.

I'll get back into sequence in my repsonces next time.

I'm getting a lot of milage out of the thread. Good for me. Keep reading, keep responding. Tell me what you think. If you don't agree with me I'm sure I'll tell you you're wrong, but tell me anyway.

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