[Liversidge]

Until recently I have only ever played duplicate but have recently started playing teams and Chicago. My partner thinks that when playing these formats I should be more prepared to take risks when bidding a marginal game or slams. I can understand the importance of not taking risks for overtricks if it might mean going off, - make sure you make your contract. But what about taking risks during bidding?
For example, suppose we are playing the weak no trump and the bidding goes 1♥-1♠-2NT (17-18) -? I have 7 HCP and 5 spades. I have assessed that my hand does not warrant an upgrade or downgrade.
In duplicate I would pass because we have at most 25 HCP and could have 24 HCP. As I understand it, on average 3NT makes with 25.5 HCP, so the probability of making game with my hand is less than 50%.

I reckon I should change my thinking when playing Chicago. If I go 1 off it’s -50/100. If I make game it’s +400/600. I can afford to go off three times out of four and still be in profit in the long term.

Am I thinking straight? And if so, does the same thinking apply when playing teams?

[Tramticket]

Chicago: Do you carry-forward part-scores in your version of Chicago? If you do, this is a topic in itself. If not then the tactics are similar for teams. Also, do you play Chicago for money?

Teams: A whole book could be written on this subject (and probably has been). But important points include:
- Bidding and making games is important - particularly vulnerable game. A vulnerable 35-40% game is a reasonable gamble. A non-vulnerable 45% game is a reasonable gamble.
- Make your games. Don't risk your contract for an over-trick - think about safety plays. Risk a an extra under-trick or two if it give a chance of making game.
- Look for the best game, not the best-scoring game. Even 5m might be sensible at teams.
- Slams are pretty neutral. The amount you gain by bidding a slam is similar to the amount you lose by going off in a slam when you could have made game.
- Grand slams need VERY good odds at any form of the game.
- Don't be overaggressive in pushing for a part-score. If opps can score 110 in 2♠, there is little point in pushing on to 3♣ conceding 100 for one-off vulnerable. This might be a good result at pairs - but is a flat board at teams.
- Don't risk big penalties - particularly vulnerable. If you go for a number at pairs after preempting or sacrificing it is just one board. At teams it can have a huge impact.

[Tramticket]

Also, the tactics in defence can be different. The objective is to defeat the contract and worrying about over-tricks is less important. Tend to be more aggressive when on lead (I say "tend" - look at the cards in your hand and the bidding as well!).

If you can see a particular holding that partner might hold which will defeat a contract, you will normally play for partner to have that holding - even if it gives away an over-trick much of the time when partner holds something else.

[Liversidge]

Tramticket, on 2018-November-30, 06:22, said:

Chicago: Do you carry-forward part-scores in your version of Chicago? If you do, this is a topic in itself. If not then the tactics are similar for teams. Also, do you play Chicago for money?

Your guidelines on Teams are very helpful, thanks.

We don't play Chicago for money. It's a social thing - we play Chicago about 8 times a year, all day events, four board rounds -None dealer dealer all - scoring each round individually. At the end of the day the raw scores are added up.
Are the percentage guidelines ( 35-40%; 45%) roughly the same with raw scoring as for IMPs?

[mikestar13]

OP's math is wrong for the Chicago part score/game decision. Let's say for easy figuring, partials are scored duplicate style and not carried over. Let's further suppose that the decision is 3♠ vs. 4♠ and you will take 9 or 10 tricks, and won't be doubled. If you stop in three spades, you score +140 or +170 regardless of vulnerability. Now if you bid 4 ♠ and take ten tricks, you score +420/+620, but your gain is only 250/450 vs. the +170 you would have scored in 3♠. Likewise if you bid 4♠ and take only nine tricks, you score -50/-100, but you loss is 190/240 vs. the +140 you would have scored. So not vulnerable, you break even at 43.2%, vulnerable you break even at 34.8%. But you should be a bit more conservative especially vulnerable, to allow for the badly-splitting hand where you get doubled and go down, sometimes more than one. If part scores carry, be more conservative, as the equity value of the partial is not precisely known, but higher than +140.

[rmnka447]

Tramticket has brought up a lot of good points about team play.

A couple more things to be aware of at team play --

o Don't double opponent part scores for penalties unless you're absolutely sure they can beat. Giving away a game swing by doubling a part score into game is often fatal.
o Make your contract includes making safety plays to ensure your result -- especially in doubled contracts.
o Some hands are ones where it's difficult to guess who's sacrificing and who's bidding to make. In these hands, if there's any doubt about beating the opponent's contract, don't be afraid to bid one more. I've seen plenty of hands where both pairs on a team bid to a game that makes and play there. And these double swing boards are usually big time match winners.
o Don't be scared to double games if you don't think your side can bid more, has had a makeable game outbid, and has a decent chance of beating the contract. If you're wrong, you're probably giving up an additional 200 points or so, but the additional value of setting the contract may be essential in offsetting the IMP loss if your partners don't find the sacrifice. (This is sort of the opposite side of the previous bullet.)

There is one point where I disagree a bit with Tramticket. He recommended "Don't be overaggressive in pushing for a part score." However, fighting for part scores IS important. If you can push the opponents up 1 level and beat them while your partners are allowed to play at the lower level and make, it results in a part score swing of 5-7 IMPs. These swings can be match winners. Of course, vulnerable, you have to be cognizant of the danger of going for a number and not compete wildly. This competing is an important part of successful team play, but may take actual playing experience to learn what works best.

It's my observation that many team matches are won by:
o bidding and making "thin games" especially vulnerable ones, and,
o winning the battle of the part scores.

Team play is also about playing good solid bridge -- bidding and making the games/slams you should, not going for telephone number sets, avoiding bad contracts, and playing good defense. If you can do that you can be very competitive in team events.