Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing E-W cards and recalculating DDA), the most N-S can take is 10 tricks in C/D, 8 in H, 5 in S, 7 in NT.
Is there a normal way (i.e.: not inventing a convention for this specific deal) to open this 2C without going overboard?
How about with a normal opening other than 2C?
Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing
E-W cards and recalculating DDA), the most N-S can take is 10 tricks in
C/D, 8 in H, 5 in S, 7 in NT.
Is there a normal way (i.e.: not inventing a convention for this
specific deal) to open this 2C without going overboard?
How about with a normal opening other than 2C?
Op 25-6-2020 om 12:35 schreef nrford100:
Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing
E-W cards and recalculating DDA), the most N-S can take is 10 tricks
in C/D, 8 in H, 5 in S, 7 in NT.
Is there a normal way (i.e.: not inventing a convention for this
specific deal) to open this 2C without going overboard?
How about with a normal opening other than 2C?
I think for most the north hand is a 2NTopening bid.
South will so bid 3NT and will often go down. Not always mind you.
For example if one opponent has spades AK10 or AK109 you will make 3NT
easy.
Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing E-W cards and recalculating DDA), the most N-S can take is 10 tricks in C/D, 8 in H, 5 in S, 7 in NT.
Is there a normal way (i.e.: not inventing a convention for this specific deal) to open this 2C without going overboard?
How about with a normal opening other than 2C?
Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing
E-W cards and recalculating DDA), the most N-S can take is 10 tricks in
C/D, 8 in H, 5 in S, 7 in NT.
Is there a normal way (i.e.: not inventing a convention for this
specific deal) to open this 2C without going overboard?
How about with a normal opening other than 2C?
... I would personally pick the 5-level contract. I'm surprised
that it normally goes down double-dummy; if diamonds split 3-2 and clubs
at worst 4-1, there are 11 top tricks and sufficient entries to take
them, so the only other risk would be an early ruff before you gain the
lead. I would have thought that it would therefore be above 50% to make
(thus worth bidding both at matchpoints and at IMPs), but maybe not?
In message <360866e2-7a39-4011-9dfd-fa9b14a3c345o@googlegroups.com>, nrford100 <cshearts@gmail.com> writes
Match Points, nobody vul., North is dealer.
N: Q4-AK92-AKT3-AQ3 (22 HCP)
S: J2-76-Q965-KJ654 (7 HCP)
Double dummy analysis shows that on average (100 iterations of mixing
E-W cards and recalculating DDA), the most N-S can take is 10 tricks in >C/D, 8 in H, 5 in S, 7 in NT.
I'm surprised, as I'd expect 5C and 5D to make far more often than not.
(And if spades divide 5-4, then you should normally make 8 tricks in
NT.) Even with a 4-1 diamond break, double dummy you can surely always
make a minor suit game unless you suffer a spade overruff on the third
round of the suit, a first round heart ruff or the clubs are 5-0.
I'm not sure if, in MPs, I would want to go to game if N-S can only
make it 5 times out of 10 (50-50). I usually just do 10 iterations
because doing 100 takes too long, but I could do 11 to get fewer ties
(6-5 instead of 5-5).
On Thursday, June 25, 2020 at 6:43:29 AM UTC-5, ais523 wrote:one:
... I would personally pick the 5-level contract. I'm surprised
that it normally goes down double-dummy; if diamonds split 3-2 and clubs
at worst 4-1, there are 11 top tricks and sufficient entries to take
them, so the only other risk would be an early ruff before you gain the
lead. I would have thought that it would therefore be above 50% to make
(thus worth bidding both at matchpoints and at IMPs), but maybe not?
Well, you've ruined my day! :-)
For a number of weeks I've been using average DDA optimum contracts to help my program make bids beyond what's in my bidding database (www.aeyec.com/BidBase), now I find out that I've screwed up.
Based on your surprise about going down double-dummy, I single-stepped through my DDA averaging code to show you a thing or two.
Following are my results. With N-S holding the big hands, I mix up the E-W cards and recalculate N-S's DDA optimums, doing this 10 times and averaging the results.
I originally decided not to round the results up, thinking that playing MPs, you don't want to bid game if the average DDA is less than game, even by a small fraction. That just seemed logical to me, so I didn't verify it by making a chart like this
N: Q4-AK92-AKT3-AQ3than 10 tricks 2 other times, then the optimum for that suit would be 10 tricks.
S: J2-76-Q965-KJ654
E W
1: K987-J5-J42-T872 AT653-QT843-87-9 C:11 D:11 Avg.: 11 11
2: K9865-85-J742-82 AT73-QJT43-8-T97 C:11 D:11 Avg.: 11 11
3: AKT876-J4-7-T972 953-QT853-J842-8 C:11 D:11 Avg.: 11 11
4: K9875-T85-87-872 AT63-QJ43-J42-T9 C:11 D:11 Avg.: 11 11
5: A65-QJT3-874-972 KT9873-854-J2-T8 C:11 D:11 Avg.: 11 11
6: A6-QT54-J8742-T7 KT98753-J83--982 C:10 D:10 Avg.: 10.833 10.833
7: K9853-QJ8-8742-9 AT76-T543-J-T872 C:11 D:11 Avg.: 10.857 10.857
8: 9876-QT83-J74-92 AKT53-J54-82-T87 C:11 D:11 Avg.: 10.875 10.875
9: AKT98-QJ54-8-872 7653-T83-J742-T9 C:11 D:11 Avg.: 10.889 10.889 10: K75-JT543-842-72 AT9863-Q8-J7-T98 C:11 D:11 Avg.: 10.9 10.9
As you can see, N-S can make 5C/D 9 times out of 10, so using the average was not good thinking.
In my own defense, I'm a total idiot when it comes to statistics, barely passing an intro course when working on an MBA.
Now my guess would be that all I have to do is determine the greatest number of tricks which could be taken at least half the time. So out of 10 mixes of E-W's cards, if N-W can take 10 tricks in a suit 6 out of 10 times, or 10 tricks 4 times and more
I'm not sure if, in MPs, I would want to go to game if N-S can only make it 5 times out of 10 (50-50). I usually just do 10 iterations because doing 100 takes too long, but I could do 11 to get fewer ties (6-5 instead of 5-5).
So am I on the right track now?
No idea what you are doing that 10 times takes a long time.
nrford100 posted 6/25/2020:enough to smooth out those things and it is fast enough to do for each deal automatically. At the very least, a 10|20-iteration run is frequently more accurate than optimums based on a single lay of the cards while a 100|200 run is often no different
"The 10|20 iterations takes about 9 seconds on average. Doing 100|200 iterations takes about 90 seconds.”
"As to how many iterations it takes to be "useful" - the things which *most* affect the optimums which are based on a single lay of the cards are whether or not finesses are on and whether or not suits split favorably. A sample size of 10 is usually
Some very basic stat reliability numbers that are on point:
100 iterations = 95% confidence with 3% error max.
75 = same confidence = 4% error max.
38 = same confidence = 8% error max.
19 = same confidence = 16% error max.
10 = same confidence = 32% error max.
enough to smooth out those things and it is fast enough to do for each deal automatically. At the very least, a 10|20-iteration run is frequently more accurate than optimums based on a single lay of the cards while a 100|200 run is often no differentnrford100 posted 6/25/2020:
"The 10|20 iterations takes about 9 seconds on average. Doing 100|200 iterations takes about 90 seconds.”
"As to how many iterations it takes to be "useful" - the things which *most* affect the optimums which are based on a single lay of the cards are whether or not finesses are on and whether or not suits split favorably. A sample size of 10 is usually
Some very basic stat reliability numbers that are on point:
100 iterations = 95% confidence with 3% error max.
75 = same confidence = 4% error max.
38 = same confidence = 8% error max.
19 = same confidence = 16% error max.
10 = same confidence = 32% error max.
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