Which bluff is better?

[tessarji]

River bluffs are in vogue on the forums today, so I'll post my attempt.

CAZ 20/40 1/2kill

Terrible 90/5/.5ish player limps UTG. Late position player calls. SB completes, I check with 8 [img]/images/graemlins/diamond.gif[/img] 7[img]/images/graemlins/spade.gif[/img].

Flop is A[img]/images/graemlins/club.gif[/img] Q[img]/images/graemlins/spade.gif[/img] 9[img]/images/graemlins/spade.gif[/img]. Everyone checks.

Turn is 6[img]/images/graemlins/club.gif[/img]. SB check, I check, UTG player bets. Folded to me, I call intending a river bluff if my draw misses.

River is Q[img]/images/graemlins/club.gif[/img]

Would you:

1. Bet out as a bluff
2. Check-raise bluff
3. Just fold you idiot

[vmacosta]

Just fold the turn.

[iggymcfly]

Why not just fire out on the turn, when it's unlikely that anyone has anything? This "play super-passive with my draw and then bluff when it's too late to represent anything good" is a classic donk play.

[HOWMANY]

[ QUOTE ]
Just bet the turn.

[/ QUOTE ]

And then bet the river. At least that's how I play it, I don't see the point of check/calling the turn and randomly bluffing the river, I would look you up with KJ/KT here probably.

[tessarji]

I agree that you might. I think that most donkeys don't think like this, and generally fold on the river without a pair.

[Hielko]

[ QUOTE ]

I agree that you might. I think that most donkeys don't think like this, and generally fold on the river without a pair.

[/ QUOTE ]
True, but I don't think you are getting a lot of pair hands to fold with this bluff.

[benwood]

It depends on what kind of terrible player UTG is.Will he bet the turn without a pair?Will he fold the river with a pair?

[danzasmack]

"Terrible 90/5/.5ish player limps UTG."

"I call intending a river bluff if my draw misses."

This is a plan I don't usually have.

[slik]

He's not folding a pair whether you donk or c/r. Being that donking is cheaper than c/r'ing, if you insist on bluffing, donking is the way to do it. Either way this should be read based, depending on whether you think he's pairless or not. So I vote for 3.

[tessarji]

To those who say 'just check-fold the turn' I feel you are undervaluing the situation, see below.

To those who say 'bet the turn' I agree that is a reasonable alternative. I chose to check because there was a decent chance it would get checked through again, and the other opponents in the hand were astute enough to judge I might be stealing and would often raise as a semi-bluff. I'd rather take a free shot at the draw.

I'll explain my thinking a little further.

This bad player is fairly passive, but even he would bet with a pair, 2nd to last to act. So he has no pair on the flop.

When he bets the turn, he has either a six, a flush draw, some other crazy draw, or air.

I have about 11-14 outs against a six. I'm getting 3:1 and I expect him to call the river. This would be a narrowly profitable call. Since I have a near zero equity call, the determining factor is if I think I will have a profitable or unprofitable bluff on the river.

I have about 10-14 outs against a higher busted hand, and I expect him to sometimes call the river. If he calls 40% of the time I would have nearly zero equity.

If he doesn't have a pair, I'm expecting to often win on a river bluff. About 20% of the time his draw will come in, and I'll lose. I'll put his chances of having a six at also about 20%.

If I donk bluff the river, I'm investing 1 bet to win 4 bets. I need a 20% success rate to break even.

If I check raise bluff the river, I'm investing 2 bets total to win 5 bets. I need a 28% success rate.

If I assume that he'll have a hand on the river 40% of the time, I need him to fold a busted hand 33% of the time to a river bet, and 46% of the time to a check-raise.

So it would appear betting out is better.

But, this doesn't consider the board texture. The river specifically puts a flush possibility and trips possibility on the board. He's a passive player and almost certain to check behind with a 6 now.

So, by waiting to see if he bets, I can determine whether a bluff is likely to succeed. His bet will indicate either a missed draw, or a flush. Let's say he bluffs 75% of the time with the missed draw. It's obvious then that _when he bets_ the proportion of missed hands to flushs will be 3:1. Investing 2 to win 5 here requires only a 28% success rate, when he has a missed hand 75% of the time. Therefore, this bluff must be successful in getting him to fold when busted 37% of the time (to break even).

Although the break-even percentages are close (37% to 33%) I believe he is more likely to fold when busted to a check-raise then a bet. If he actually folds his hand 60% of the time to a bet, and 80% of the time to a check-raise, then the check-raise is 150% as profitable as a bet.

Therefore I would elect to check-raise.

The disadvantage of course is when he checks behind I certainly lose.

I haven't done a complete analysis but the dominating condition seems likely to be how often he bluffs with a missed draw. If he bluffs 100% of the time, the check-raise bluff is far superior (because he has no hand when betting a higher percentage, and he puts more money in the pot). If he bluffs only 10% of the time then betting out is much better for obvious reasons.

Results:

I checked and he bet. I check-raised, and he folded.