Improving Hand Evaluation Part 3
tys...@yahoo.com
http://tinyurl.com/25huc
[Improving Hand Evaluation Part 2]
http://tinyurl.com/383e6
Parts 1&2 are a little long and complicated, so feel free to skip them
if you're not a nerd. This Part #3 is what brings the concepts in 1&2
together and presents them in a much simpler way.
SUMMARY: This is (yet another) evaluation method to help quantify hand
evaluation and reach more accurate contracts. This is a simple and
easy-to-use method, yet provides more accuracy than many other
"improved" methods.
This is an attempt to convert Evolved Binky Points into some formulas
that are easier to remember than huge tables of numbers. This took a
lot more work than I had initially thought. Trying to find a method
that is more accurate that HCP, but doesn't use a lot a complicated
fractions is just about impossible. In order to keep things simple
I'm avoiding fractions wherever I can, but it means there's a slightly
different scale of strength. I initially tried to make this scale to
"normal points" so an average 13-point hand would be about 13 points
in the new system. I just couldn't do it without fractions that would
be almost impossible to keep straight at the table. This new
distribution has ~1.5 times the scale of normal points, so to convert
these to "normal" subtract a third. To convert from normal to these
values, multiply by 1.5.
A typical opening hand for standard methods should have ~19 points.
You should typically need:
34 for the 3-level
39 for the 4-level
44 for the 5-level
49 for the 6-level
54 for the 7-level
Of course these are just guidelines, like the 26 points typically
needed for game. Certain scoring situations (like vul at IMPs) may
push you to change these recommendations.
Here is my new method of hand evaluation:
HONOR POINTS (HP):
A = 6
K = 4
Q = 2
J = 1
(This is just HCP + Controls)
* Add 1 point for every suit that has 2+ honors (including the Ten)
* Doubletons: Don't add the point for 2+ honors and subtract one
additional point for QJ. (Don't subtract one for Qx or Jx as these are
already valued low enough)
* Singletons: Honors are valued as the next weakest honor (A=4, K=2,
Q=1, J=0)
DISTRIBUTION:
Add points for both shortness and length
* Shortness points: 5/3/1 for void/singleton/doubleton
* Length points: 1 point for each card over 4 in a suit
REVALUATION (AFTER PARTNER BIDS)
This is a complicated matter and I'm working on a lot of different
things to try and come up with an easy to use metric. For now use
this simplified way:
* Don't count shortness in partner's suit (unless you find an 8-card
fit elsewhere)
* Give +2 bonus for each trump you have over an 8-card fit
EXAMPLES:
KQJxx
-
QJxxx
AJT
* Initially: 14 HCP + 3 controls + 3 suits with 2+ honors = 20 HP. 5
for the void and 2 for the 5-card suits = 27 total points.
* Partner bids spades: +4 for the 10-card fit = 31 points.
* Partner bids hearts: – 5 for the void in partner's suit = 22 points.
Kxx
Qx
JTxx
ATxx
* Initially: 10 HCP + 3 controls + 2 suits with 2+ honors = 15 HP. We
get 1 distribution point for the doubleton = 16 total.
* Partner bids spades: No change = 16 total.
* Partner bids hearts: -1 for the doubleton = 15 points.
For NT contracts you can still use these HP, but for distribution
simply count 1 point if you have a 5+ suit. You should need about:
34 HP for 2NT
37 HP for 3NT
44 HP for 6NT
48 HP for 7NT
Now all I need is a snappy name for my evaluation system. Since my
initials are TS, I'll call them TS points, or TSP. That will do for
now I guess.
COMPARING EVALUATORS
I'll extend my previously posted table of evaluator comparisons to see
how much improvement you can expect by using this method:
ERROR SCORE
HCP 1.23 -0.49
HCP+321 1.07 0.00
HCP+531 1.05 0.07
Zar 1.05 0.08
BUMRAP+321 1.03 0.14
BUMRAP+531 1.02 0.21
TSP 1.02 0.21
Binky 0.99 0.32
ERROR is the average # of tricks there is in difference between how
many tricks we think we can take and how many we actually take.
SCORE is an estimation of the IMPs/board we expect to gain against a
team that uses a simple HCP+321 evaluation method. It's a measure of
how much payoff there is for using a better evaluation system.
HCP is A=4, K=3, Q=2, J=1
HCP+321 is HCP + 3 per void + 2 per singleton + 1 per doubleton
HCP+531 is the same with more points assigned to shortness
Zar is HCP + Controls + twice the length of longest suit + once the
length of second-longest suit minus length of shortest suit.
http://public.aci.on.ca/~zpetkov/
BUMRAP is a substitute for HCP: A=4.5, K=3, Q=1.5, J=0.75, T=0.25
TSP is the method described in this article. It's an attempt to find
the best evaluator using simple whole numbers.
Binky is Thomas Andrew's evaluator:
http://thomaso.best.vwh.net/bridge/valuations/
Mike Bell
tys...@yahoo.com wrote:
[big snip]
> COMPARING EVALUATORS
>
> I'll extend my previously posted table of evaluator comparisons to see
> how much improvement you can expect by using this method:
>
> ERROR SCORE
> HCP 1.23 -0.49
> HCP+321 1.07 0.00
> HCP+531 1.05 0.07
> Zar 1.05 0.08
> BUMRAP+321 1.03 0.14
> BUMRAP+531 1.02 0.21
> TSP 1.02 0.21
> Binky 0.99 0.32
Cheers Tysen, very interesting.
Two points - firstly, after all that, your comparison shows little
difference between TSP and BUMRAP+531. Any ideas why this is? Could it
be that giving the ten a small value is significant enough to match all
the other changes you suggest?
Secondly, you seem to have gone down the Zar route of suggesting opening
a lot of hands with a couple of top honours and a bit of distribution. I
am convinced this approach is wrong. Say you are dealt Axxxx Axxxx xxx
void. Sure, your hand is great if you find a fit, and there is more
likely to be one than not. But if you pass on the first round, you can
come in on the second round and still reach your major game. If you open
the hand and there is a misfit, you are likely to get far too high and
you won't be able to do anything, as the shape and the top honours are
worth far less in no trump. Even so, Axxxx Axxxx xxx void is close to an
opening bid for me. What I cannot understand is the suggestion that void
xxx Axxxx Axxxx should also be opened. When you open a minor suit, you
are primarily showing strength for playing in 3NT, so why show that when
you don't have it?
Cheers
Mike
tys...@yahoo.com
> In message <a1bce703.04052...@posting.google.com>
> tys...@yahoo.com wrote:
> Cheers Tysen, very interesting.
>
> Two points - firstly, after all that, your comparison shows little
> difference between TSP and BUMRAP+531. Any ideas why this is? Could it
> be that giving the ten a small value is significant enough to match all
> the other changes you suggest?
They are practically the same evaluator, just with different scales.
When I've looked at it, the value of the Ten is pretty insignificant.
TSP and BUM+531 are very close in performance, but of course TSP
doesn't use fractions, which was the whole point.
> Secondly, you seem to have gone down the Zar route of suggesting opening
> a lot of hands with a couple of top honours and a bit of distribution. I
> am convinced this approach is wrong. Say you are dealt Axxxx Axxxx xxx
> void. Sure, your hand is great if you find a fit, and there is more
> likely to be one than not. But if you pass on the first round, you can
> come in on the second round and still reach your major game. If you open
> the hand and there is a misfit, you are likely to get far too high and
> you won't be able to do anything, as the shape and the top honours are
> worth far less in no trump. Even so, Axxxx Axxxx xxx void is close to an
> opening bid for me. What I cannot understand is the suggestion that void
> xxx Axxxx Axxxx should also be opened. When you open a minor suit, you
> are primarily showing strength for playing in 3NT, so why show that when
> you don't have it?
To each his own. It depends on what you think the point of an opening
bid is. If you use sound methods and your goal is to be constructive
so you can reach the best games and slams, then that's great. My
personal philosophy is to use opening bids to get the first word in
before the opponents do. Shapely hands (especially 2-suiters) need the
most bids to adequately describe themselves. You've got to start
describing as soon as possible while the bidding is low. If your opps
find a fit before you do, it may be too late. I'm personally fond of
light opening systems on shapely hands and will gladly open 1H on xx
KTxxx xx AJxx. But partner knows I will have hands like this and won't
blindly go to 3NT. But he can preempt much more often in hearts since
I'm opening much more often than other pairs...
Miko Lee
I've read all your articles and I must say I'm impressed. I'm glad to
see you've came up with a solution that us mere mortals can use at the
table though.
One question: can you look into how evaluations change with opponents'
bidding? I think a lot of us have been told to increase the value of
AQ if RHO bids the suit and decrease it for RHO, but it would be nice
to get so quantification to this advice.
tys...@yahoo.com
> bidding? I think a lot of us have been told to increase the value of
> AQ if RHO bids the suit and decrease it for RHO, but it would be nice
> to get so quantification to this advice.
I'm actually working on this as we speak. This will be what I will
call "part 4" of the series. I'm almost done and it has some
surprising results. I hope to get this posted in about a week or so.