[luis]

Quote

If you are playing Raptor (which I prefer to standard 1NT overcalls), then the auction is going to start

(1H) - 1NT - (P) - 2S
(P) -

At this point in time, if the 1NT bidder choses to make a game try, he should do so by bidding 3C and showing his suit rather than 3S.

This is an interesting sequence for Raptor players.
First of all if the 1NT overcall is normal in strength then overcaller passes 2s so when he makes a game-try he's showing extra-values.
I think that the best approach here is:
2N = 5431 good hand, stopper in h and 5m. This allows a flexible continuation:
3c = Value in clubs, accept 4s inv if suit is clubs if suit is not clubs advancer can correct to 3NT.
3d = Value in diamonds, accept 4s inv if suit is diamonds if suit is not diamonds advancer can correct to 3NT
3h = General acceptation, now 3s=slam try, 3N=choice of games, 4m=suit and Slamish.
3s = Signoff, not interested in game.
3N = To play
3c = 5431, with 5c and SPL in diamonds, no stopper in h
3d = 5431 with 5d and SPL in clubs, no stopper in h
3s = INV with 5422 hand
Because overcaller cannot have a singleton in hearts and a good 5431 hand or he would have doubled 1h instead of bidding 1NT.

Just an idea....

Luis

[hrothgar]

In a previous posting Ben provided the following quote from Robson and Segal:

“You may be surprised to learn that there is another sort of forcing pass in fit auctions that lays no claim to the hand. Often, in fact, it will be clear that the hand belongs to your opponents….

Using an ‘idle’ bid: We will start with a fairly simple auction: 1S – (P) – 3C – (3D); P – (P) – ? Your 3C bid showed a fit-raise to the three level; so should you now bid 3S automatically and go back to sleep? Would you ever pass?....

Obviously it would be a strange state of affairs if you allowed the opposition to play 3D undoubled on this sequence. After all, you’ve already announced an offensive raise to 3S.”

I have enormous respect for Robson and Segal as bidding theorists, however, I think that they are making a fundamental analytic error during their analysis. Maybe this is a result of my training as an economist, however, R+S appear to be guilty of the “sunk cost” fallacy. One of the cardinal sins of economics is allowing emotion to sway analytic logic. Consider the following example:

I have an investment opportunity. The opportunity has a 50% chance to pay $2000 and a 50% chance to pay $1000. The expected value of this investment opportunity is $1500. Suppose that the total cost of this investment opportunity is $1600. In this case, I should reject this opportunity in favor of some alternative investment since the expected return is -$100.

Now consider the following extension: The investment opportunity is actually the last stage of a long and expensive process. I have already spent $500 bringing this project towards fruition. I am now debating whether or not to invest in the final stage of the project or walk away completely. Here, once again, I am presented with the same investment opportunity. Economic logic states that here, once again, I should walk away from the investment. However, many individuals become emotionally involved with the fixed cost of the investment. They feel that they need to follow through with the project to “redeem” the $500 that they originally invested. Individuals “throw good money after bad”. I would argue that this hypothetical example is very much analogous to the bidding situation that we are examining.

At this point in time, I would like to focus on one particular point that R+S raise: “Obviously it would be a strange state of affairs if you allowed the opposition to play 3D undoubled on this sequence. After all, you’ve already announced an offensive raise to 3S”. This phrase embodies the sunk-cost fallacy. Responder’s 3C fit jump is a calculated gamble. The 3C fit jump serves a number of crucial purposes:

1.   The fit jump immediately informs opener whether there is a double fit
2.   The fit jump deprives the opponents of bidding space to describe their hand

However, the fit jump does not guarantee sufficient strength that opener is guaranteed to make 3S. [If your partner is able to make 3S 100% of the time, even opposite a club misfit, then you probably aren’t making fit jumps nearly often enough]

In short, the 3C bid is best modeled as a gamble. I am willing to “invest” in a fit jump because I believe that this action is my best investment opportunity. However, once the opponents interfere in the auction, my original decision to force the auction to 3S should not have any impact on my optimal bidding strategy.

Obviously, having a partnership agreement that pass is forcing and the auction can not die below 3S has the advantage of simplicity, however, it is very unclear whether this is in any way “optimal” from a theoretical perspective.

[Free]

Quote

I have an investment opportunity. The opportunity has a 50% chance to pay $2000 and a 50% chance to pay $1000. The expected value of this investment opportunity is $1500. Suppose that the total cost of this investment opportunity is $160. In this case, I should reject the opportunity in favor of some alternative investment.

Now consider the following extension: The investment opportunity is actually the last stage of a long and expensive process. I have already spent $500 bringing this project towards fruition. I am now debating whether or not to invest in the final stage of the project or walk away completely. Here, once again, I am presented with the same investment opportunity. Economic logic states that here, once again, I should walk away from the investment. However, many individuals become emotionally involved with the fixed cost of the investment. They feel that they need to follow through with the project to “redeem” the $500 that they originally invested and “throw good money after bad”. I would argue that this hypothetical example is very much analogous to the bidding situation that we are examining.

Euhm, I could be wrong, but I think you made a mistake in your logic here. If you allready payed $500, you actually should invest the other 1100. If you get the $1500 back, you'll only lose $100 and if you don't invest you lose $500... Correct me if I'm wrong plz.

[hrothgar]

Opps

BAD typo here
Change the cost of the investment opportunity to $1600, NOT $160

[inquiry]

To Richard, RE: Financial calculations and bridge

I am just a poor bridge player, in more ways than one. So mixing financial models into discussion of bidding auctions confuses me both from a bridge standpoint and from a money laundrying view.

Let me say what I realize. I realize that using PFA (principle of fast arrival) here is not standard treatment. I realize that many people will never accept this treatment, and I am certainly fine with that (more imps for me). And finally, I realize that your model is flawed, in addition to typo you admitted.

Here is the situation. When you pass with a good hand (rather than bidding on), you open the door for a reopening double by your partner which turns your initial investment at the three level into a huge windfall. If you have to BID with all good hands (excluding a double when you are well heeled in their suit), you will miss the opporuntity for many great scores when your partner reopens with a double. The PASS keeps you flexible right when you need you, when you have a good hand.

Second model flaw, is that if you bid with the bad hands, you actually hinder the opponents right when you need to do so... when it may actually be their hand rather than yours. And you do so when you have a fit that is presumably "LAWFUL". So even if you are going down, and that can not be certain, you are "protected" as it was by LOTT. Third, the forcing pass allows a reopen double or maybe redouble which can REALLY come in handy on exploring for slam below game, while bidding 3 of the major or 4 of the major gets the bidding high without much real help in evaluating what is going.

So, I suspect the flaw in your investment analysis is to cconsider this a two option situation: after 3C you will make 3S or you will not. In fact, after 3C if they bid you might make 7S, 6S, 4S, 3S, 3Dx down tons, or go down in 3S yourself. If your 3S make is 2000 and your 3S down is only 1000, what value do you give to 3Dx down three or 4S or 6S or 7S, all made easier by the pass to show a better hand. And the 3Dx is not reachable if you bid with goodish hands.

Now, is the R/S way the only way? Of course not. But it is a bidding philosophy that has been very effective for me and which fits my personal style very well. It clearly is not for everyone.

Ben

[inquiry]

Quote

Quote

If you are playing Raptor (which I prefer to standard 1NT overcalls), then the auction is going to start

(1H) - 1NT - (P) - 2S
(P) -

At this point in time, if the 1NT bidder choses to make a game try, he should do so by bidding 3C and showing his suit rather than 3S.

This is an interesting sequence for Raptor players.
First of all if the 1NT overcall is normal in strength then overcaller passes 2s so when he makes a game-try he's showing extra-values.
I think that the best approach here is:
2N = 5431 good hand, stopper in h and 5m. This allows a flexible continuation:
3c = Value in clubs, accept 4s inv if suit is clubs if suit is not clubs advancer can correct to 3NT.
3d = Value in diamonds, accept 4s inv if suit is diamonds if suit is not diamonds advancer can correct to 3NT
3h = General acceptation, now 3s=slam try, 3N=choice of games, 4m=suit and Slamish.
3s = Signoff, not interested in game.
3N = To play
3c = 5431, with 5c and SPL in diamonds, no stopper in h
3d = 5431 with 5d and SPL in clubs, no stopper in h
3s = INV with 5422 hand
Because overcaller cannot have a singleton in hearts and a good 5431 hand or he would have doubled 1h instead of bidding 1NT.

Interesting idea Luis. I saw where someone posted that this raptor auction was "blocking" (1H)-1NT-(P)-2S; (P)-3S

I disagree with that. you don't go raising with a four card suit to block your opponents. Heck, your partner may have as few as 3 spades on this auction. So 3S is clearly a game try.

I separate my game tries, not as accurately as you suggested. My 3S raise shows 5 loser hand (I pass with more), and my other bids show either more shape or fewer losers and are forcing, while 3S can be passed. I admit my game tries are either 2NT or 3S over a 2S bid by partner (let them figure out where my minor is). But sometimes I get dealt a six card minor or a seven card minor, which is when I make the game try in the minor. I do, however, like your response tree to 2NT. I will give that some thought and look at old hands to see how it does.

ben