From: bs@gauss.mitre.org (Robert D. Silverman)
Newsgroups: rec.games.bridge
Subject: Re: Bid this hand
Date: 9 Apr 92 15:49:56 GMT
Article-I.D.: linus.1992Apr9.154956.29680
Organization: Research Computer Facility, MITRE Corporation, Bedford, MA

In article <1992Apr9.140018.6481@magnus.acs.ohio-state.edu> apearlma@magnus.acs.ohio-state.edu (Andrew Pearlman) writes:
 
Our 'rn' program had a problem and bollixed up my original reply to
this post. I am sending it again. Sorry for sending out a post that
was just a repeat of a prior one.

:In article <1992Apr9.122131.22605@linus.mitre.org> bs@gauss.mitre.org (Robert D. Silverman) writes:
:>In article <1992Apr7.163841.9125@magnus.acs.ohio-state.edu> apearlma@magnus.acs.ohio-state.edu (Andrew Pearlman) writes:
:>:In article <1992Apr1.114022.9957@linus.mitre.org> bs@faron.mitre.org (Robert D. Silverman) writes:
:>:>In article <1992Apr1.052156.17144@magnus.acs.ohio-state.edu> apearlma@magnus.acs.ohio-state.edu (Andrew Pearlman) writes:
:>:>:
:>:>:You have this hand:
:>:>:S K10x
:>:>:H A2
:>:>:D AKQ1098
:>:>:C Ax
:>:>:
:>:>:Bidding goes
:>:>:2H(weak2)-?
:>Huh? Where do you get 8 tricks from?? You get a heart lead and your
:>stopper is knocked out. You cash diamonds and they DON'T BREAK. LHO
:>wins the J diamonds puts partner in with A spades and the 2H bidder
:>cashes a bunch of hearts. They take a diamond, 5 hearts and A spades.
:>Down 3.
:
:RHO opponent can not possibly have diamonds stopped.  So he is relying on
 
Huh? Can you read?? I said  LHO not RHO wins J diamonds.

:partner to have A) 4+ diamonds and B) the J of diamonds.  Assuming a void
 
He isn't relying on anything. He looks at his hand, sees solid hearts
with a guaranteed reentry (A spades), sees that the minors are NOT breaking
and so has a first rate double.

This is not to say that he is guaranteed to beat 3NT. Merely that on the
average it is a winning proposition to double.

:in RHO, there is roughly a 50% of A and a 50% of B.  i.e. there is only
 
Disciplined players do not open weak two's with side suit voids.

And you have no basis for assigning any probabilities to anything 
except that the double makes it VERY likely that minors are not
breaking.  And even if they DO break, you STILL only have 8 tricks.
(down 1 redoubled = -400!).

I suggest you go read S.J. Simon's "Why you lose at bridge" and read 
his chapter on the mathematics of doubling.

What do you hope to gain by your redouble??  If it's right you
gain 400 points. [400 vs 100 for 3NT plus 100 for redbled contract].
If it's wrong you can lose 1600. That's 4:1 against you, so your
redouble has to be right 4 times out of 5 just to break even.


:While the odds are not entirely cumulative, they are heavily in my favor.
 
The fact that a competent RHO doubled makes it strongly in THEIR favor.

If you believe otherwise fine. Nothing I can say can convince you.

In fact, I don't know why I am wasting my time. I have already gotten
private email suggesting that arguing with you is a waste of time.

:I feel that while your point is valid(and thought of), it is too conservative
:for me.
 
And there you have it folks! My point is valid, but too conservative
for him.

Hey! If you like -1600 numbers that's fine with me too!  

Would you like to play some rubber bridge for money?? Say $.25/point???  :-)

--
Bob Silverman
These are my opinions and not MITRE's.
Mitre Corporation, Bedford, MA 01730
"You can lead a horse's ass to knowledge, but you can't make him think"