Pre-emptive Bidding -- Does Vulnerabilitity Matter?

WARNING! The following post talks about Pre-emptive Bidding. Pre-empts are bids used by more experienced players. If you are a new player do NOT bother reading this post. When you have played a bit more and know a bit more you can learn how to use them. For now, do not bother.

Please read these posts first to learn a little bit about pre-emptive bidding:
Pre-emptive Bidding -- An Introduction
Responding to a Weak 2

Question: Does vulnerability make a difference when making a pre-emptive bid? Why does that even matter?

Answer: Vulnerability is HUGE! The reason for that is the scoring. First check out my post on:
How to Score at Matchpoints

Now let's see what happens if you go down in your contract. This is the amount of points you give your Opponents if you go down in your contract.

# Tricks you went DOWN in your contract	Non-Vulnerable	Vulnerable
1	50	100
2	100	200
3	150	300

Now let's see what happens if you go down in your contract and the Opponents DOUBLE you.

# Tricks you went DOWN in your contract DOUBLED	Non-Vulnerable	Vulnerable
1	100	200
2	300	500
3	500	800

The BIG number on both these charts is the minus 200.

Minus 200 is a score you never want to get in matchpoints.

Why? Because if you give away 200 points to the Opponents that is a number they will never get for any part score they bid. Sometimes making a pre-emptive bid means you "steal" the contract from the Opponents. So they were going to bid on the contract but you stopped them because you bid too high, too fast for them. This generally means that you will not make your contract. After all, it should not have been yours. The Opponents have the majority of the points. You were just bidding because you had length in your suit. So now let's look at what would happen if you did NOT steal the contract from the Opponents. Rather you had let them bid instead. How many points would you have given away?

If you let them bid 2♠ and take 9 tricks they will get 140 points. Even if they bid 2♠ and take 10 tricks they will still get only 170 points. Neither of these scores beats giving them 200 points. If the Opponents could be in a minor suit (say 3♣) even if they take all 13 tricks they only score 190 points. You would rather give them 190 points versus 200 points.

That means that unless the rest of the Opponents can not only bid but also make a game if you give your Opponents 200 points you will get a bad score at matchpoints. You were better off NOT bidding and just letting them play in their part-score.

That also means that if you go down 2 in your vulnerable contract that is a bad result for you unless the other Opponents bid and make a game.

If the Opponents manage to double you in your vulnerable contract and you just go down 1 trick that is a bad result for you unless others bid and make a game.

What about if the Opponents can bid and make a game?

Well now you need to check out the Opponents vulnerability. If they Opponents are NOT vulnerable (but you are) then you are allowed to go down only one doubled. If the Opponents double you and you go down two tricks the Opponents score 500 points. If they can bid and make 3NT they would only score 400 points since they are not vulnerable. If they can bid 4♥ and take 11 tricks they only score 450 points since they are not vulnerable.

So here's a chart:

Opponents Vulnerability	You are Non-Vulnerable	You are Vulnerable	You are Non-Vulnerable but DOUBLED	You are Vulnerable and DOUBLED
Non-Vulnerable	You can go down one for sure -- that's only 50 points and that will beat any part-score. If you can go down two you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor	If you can go down one you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor. If you go down two the rest of the Opponents have to bid and make a game for this to be good for you.	If you can go down one you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor. If you go down two the rest of the Opponents have to bid and make a game for this to be good for you.	If you can go down one you'd better make sure the rest of the Opponents can bid and make a game. If you go down two the rest of the Opponents need to bid and make a slam for this to be good for you. Very unlikely.
Vulnerable	You can go down one for sure -- that's only 50 points and that will beat any part-score. If you can go down two you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor	If you can go down one you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor. If you go down two the rest of the Opponents have to bid and make a game for this to be good for you.	If you can go down one you'd better make sure the Opponents can take at least eight tricks in NT or a major or nine tricks in a minor. If you go down two or three the rest of the Opponents have to bid and make a game for this to be good for you. Going down four will be bad.	If you can go down one you'd better make sure the rest of the Opponents can bid and make a game. If you go down two the rest of the Opponents have to bid and make a game for this to be good for you. Going down three will be bad.

That's an INCREDIBLY difficult chart to memorize!

This is true. Don't bother. Here's an easier way to think of it:

Vulnerability	Meaning	Therefore
FAVOURABLE vulnerability	YOU are not vulnerable but the Opponents are vulnerable	You can go down THREE
EVEN vulnerability	You have the same vulnerability as the Opponents -- either both non-vulnerable or both vulnerable	You can go down TWO
UNFAVOURABLE vulnerability	YOU are vulnerable but the Opponents are not vulnerable	You can go down only ONE

In general just remember that if you are VULNERABLE make sure you have a GOOD suit and be a little more timid in the bidding. You shouldn't get into too much trouble that way.