Key holdem odds to memorize

[Derek in NYC]

I initially posted this in small stakes, where I participate, but then I remembered this forum.

I thought this might be a helpful thread for many players, myself included. I actually have a set of about 40 flashcards that I sometimes review on the bus when Im bored. Anyhow, I thought I'd tap the 2+2 talent pool to increase my flashcards. So here goes my first helpful odd to get the list going:

Odds of flopping a flush draw or made flush with 2 suited cards: 8:1 against

(By the way, does anybody know the odds of flopping two pair or trips holding two unpaired cards?)

[knsmith85]

[ QUOTE ]
I initially posted this in small stakes, where I participate, but then I remembered this forum.

I thought this might be a helpful thread for many players, myself included. I actually have a set of about 40 flashcards that I sometimes review on the bus when Im bored. Anyhow, I thought I'd tap the 2+2 talent pool to increase my flashcards. So here goes my first helpful odd to get the list going:

Odds of flopping a flush draw or made flush with 2 suited cards: 8:1 against

(By the way, does anybody know the odds of flopping two pair or trips holding two unpaired cards?)

[/ QUOTE ]

I'm not sure I understand the usefulness of a lot of these ratios. Sure, knowing how often you'll flop your set, or hit your flush on the turn/river is useful, but past that this kind of knowledge seems pretty limited to me.

For example, when holding un-paired cards, what good does it do you to know how often you flop trips? First off, it is so small that you'll never be able to consider this probability in terms of pot odds, and secondly when you do flop trips you still don't know if it's any good (example: you hold 7 [img]/images/graemlins/club.gif[/img]2 [img]/images/graemlins/diamond.gif[/img], flop comes 7 [img]/images/graemlins/spade.gif[/img] 7 [img]/images/graemlins/heart.gif[/img] 8 [img]/images/graemlins/heart.gif[/img]).

This kind of thing is absolutely necessary in blackjack, but it seems to me that there is limited use in hold 'em. (You'd be much better off teaching yourself speed-arithmetic tricks than you are memorizing flashcards, IMO)

Thanks,
Kyle

[gaming_mouse]

Hey Derek,

The chance of flopping a two pair which uses both your cards is 1 in 50, and the chance of flopping trips is about 1 in 77.

2 pair: 9*44/ncr(50,3)=.0202

trips: 3*2*44/ncr(50,3)=.013


Practically speaking, the odds of flopping 2 pair or trips are so low as to be negligible. This is why playing hands like J5o is unprofitable even from the small blind with 8 limpers and a guaranteed check from BB.

Whenever you think to yourself, "Hey, there's always the chance I flop 2 pair," toss your cards in the muck.

gm

[Megenoita]

I think this thread has tremendous potential for value. Derek, I would love to know the contents of your flash cards...could you post or PM? Maybe that's too much of a hassle. It's cool...

Gaming Mouse...you're the man, dude...I love your responses. What limits do you play--just curious. Also, how do I do your computations (that you just wrote) on a retarded calculator? Sorry, I really don't know.

I'll chime in by saying that I think the Super System section on probability that no (other) player has an ace is valuable when you get down to LP play...

M

[Derek in NYC]

to use your example, you are dead wrong if you dont understand why such odds are important to memorize. suppose you hold a trash hand like 8 T offsuit, from the small blind, in a 1/2 structure. 7 players limp ahead of you. should you complete? assuming the bb does not raise, the pot is paying you 17:1 to complete. the only way to know whether this is likely to be worth playing is to know the odds i just mentioned.

[knsmith85]

[ QUOTE ]
Hey Derek,

The chance of flopping a two pair which uses both your cards is 1 in 50, and the chance of flopping trips is about 1 in 77.

2 pair: 9*44/ncr(50,3)=.0202

trips: 3*2*44/ncr(50,3)=.013


Practically speaking, the odds of flopping 2 pair or trips are so low as to be negligible. This is why playing hands like J5o is unprofitable even from the small blind with 8 limpers and a guaranteed check from BB.

Whenever you think to yourself, "Hey, there's always the chance I flop 2 pair," toss your cards in the muck.

gm

[/ QUOTE ]

I don't quite follow how you get that percentage for 2-pair. The combination on bottom makes sense to me, but I don't really get the numbers on top. Aren't there 6 cards that help you at first, 3 for the second, and on the third card (note: Order shouldn't matter here) any of 43 cards (52 - hole cards - card #1 - card #2 - 4 cards that would give you full house = 43) will do.

So for that, I'd get 6*3*44/NCR (50,3), or 18*44 / 19604 = 0.0404.

Where am I going wrong?

Thanks,
Kyle

[knsmith85]

[ QUOTE ]
to use your example, you are dead wrong if you dont understand why such odds are important to memorize. suppose you hold a trash hand like 8 T offsuit, from the small blind, in a 1/2 structure. 7 players limp ahead of you. should you complete? assuming the bb does not raise, the pot is paying you 17:1 to complete. the only way to know whether this is likely to be worth playing is to know the odds i just mentioned.

[/ QUOTE ]

Well, as was mentioned, the odds are so insignificant here for a direct hit on the flop (straight, two pair, or trips) [using the numbers from earlier, the odds of ANY of these are (1 - (1 - .013) * (1 - .0202) * (1 - .0199)) or 5.22%, you're NEVER going to have the direct pot odds to make the call here. I think you're going to lose more on second-best hands than you will make from callers to the river, so that effectively cancels out the implied odds.

[knsmith85]

[ QUOTE ]
to use your example, you are dead wrong if you dont understand why such odds are important to memorize. suppose you hold a trash hand like 8 T offsuit, from the small blind, in a 1/2 structure. 7 players limp ahead of you. should you complete? assuming the bb does not raise, the pot is paying you 17:1 to complete. the only way to know whether this is likely to be worth playing is to know the odds i just mentioned.

[/ QUOTE ]

You're much better off understanding the underlying calculations for these types of situations than you are memorizing, so you can do the math on the fly.

[Derek in NYC]

I was hoping not to have to sit down and do the math, but I dont think you're right. Given unsuited cards, there is some combination where it makes sense to complete from the SB, and perhaps limp from the button behind enough limpers. i want to know where this point is. you're right though, i should consider not only the odds of flopping two pair or trips, but also the odds of flopping a str8 or OESD given an x-gapper. my intuition tells me that some situations arise in limit poker where completing from the sb/button is the correct move, but i can't tell you what the cutoff point is. im happy to be proven wrong, and if so, im happy to concede that this may not be the greatest flashcard in the world, but otherwise, i think the utility of memorizing certain basic odds is quite important to good potodds based play.

[Derek in NYC]

by the way, why would you multiply these probabilities? shouldnt they be added?