Join Bridge Winners
Bridge Leads for Typewriting Monkeys
(Page of 7)

This is the working title for my next book. It was going to be Bridge Leads for Dummies, but my target market has a lower IQ.

Two years ago, I wrote "Statistically, What is the Best Opening Lead in a World Pairs Event?" (SWITBOL). Please read that article for context here: https://bridgewinners.com/article/view/statistically-what-is-the-best-opening-lead-in-a-world-pairs-event/

The article covered the opening leads at the World Open Pairs event in Wroclaw, Poland, 2016. I will compare that article and its predictions against the World Open Pairs in Orlando in 2018. We only have the data for the first 3 days in Orlando, but this is enough for some preliminary results. Will see if the results hold up for the rest of the event. I have only analyzed the data from the Open. Will look at adding the Seniors and Ladies events. Will see if SWITBOL holds up for those events.

The premise of the original SWITBOL article was that bridge players at a World pairs event are so bad at making opening leads that a trained monkey with a typewriter could do better.

The monkey needs the typewriter because monkeys can't speak and I haven't trained my monkeys to use a tablet yet. Completely unrelated, the WBF Executive played a bridge event yesterday entirely on tablets. The results are not on-line yet. I will see if I can get a copy of the data from that event to see if I should offer them a challenge match against my monkeys. I may need to finish the companion "Bridge Bidding for Typewriting Monkeys" and "Bridge Play for Typewriting Monkeys" books first. If it happens, does anyone know where I can borrow some research monkeys for a few days?

There were the SWITBOL statements from 2016:

Facts:

1. The one card that produces the best matchpoint score was the least led card by the players at the event.

2. A monkey with a typewriter could make better leads.

3. Best card to lead scores 56%, worse card scores 42%. Players picked the worse card more than the best card.

4. Reading this article could improve your matchpoint scores on opening lead by 14%!

5. Should you lead trumps against a major suit contract? What about leading trumps to a minor suit contract? Yes, there is a difference! Works for one but not the other. Do you know which is which?

These are the statements for 2018 (with 3 days of results):

Facts:

1. The one card that produces the best matchpoint score was the 45th least led card by the players at the event.

2. "A monkey with a typewriter could make better leads". This is partially true, however I need to get the hand record data in a binary format from WBF before I can validate this statement for Orlando. They are working on it (thank you WBF!!).

3. Best card to lead scores 57%, worse card scores 44%. Players picked the worse card more than the best card. Still true. Need to get more people to read this article.

4. Reading this article could improve your matchpoint scores on opening lead by 13-14%! Still true. Even more reason to read this article.

5. I haven't run the data yet. Give me time.

In SWITBOL, I introduced two new concepts, "BANNER leads" and "Hammond Leads".

A BANNER lead is "Black always nine, never eight red". If you have a black nine, lead it. Never lead a red eight.

How does this work?

The number in brackets is the card's position in order of lead that scored the highest percentage points.

In Wroclaw, leading the 9 (1) scored 56.1%, the 9 (3) scored 54.7%, the 8 (51) scored 42.7% and the 8 (52) scored 45.7%.

The data from Wroclaw predicted that these were the good (and bad) leads.

So far, in Orlando, leading the 9 (24) scored 50.7%, the 9 (22) scored 50%, the 8 (47) scored 46.5% and the 8 (45) scored 46.5%.

Black nines are still good, but not as good as they were in Wroclaw.

They still score above 50%.  Red eights are still bad, very bad.

Never lead a red eight.

Here's the current data from Orlando: http://www.bridgescoreplus.com/news/orlando_2018_lead_card.html

SWITBOL made the additional suggestions:

The CoS remains an unpopular card to lead, and for good reason. Scores below 49%.

The 8 was recommended as the safest lead based on data from Wroclaw. In Orlando, this card generates the highest score - 57.6%.

The K remains the most popular card to lead. True in Wroclaw, true in Orlando. But why? In Wroclaw you scored below 50% if you led that card. In Orlando, it only scores 48%. Don't lead the K. Unless you are playing against me.

From SWITBOL, "Hammond Leads ...  barring any other information, that I would lead the first card I had from the following: 9, 10, 9, J, Q, A, 3, 10, A"

This was written two years ago.

Do you think this would hold true for another tournament?

How about a simple test: 28 cards generate a matchpoint score of greater than 50% so far in Orlando.

Before you look at the next page, guess how many of the 9 cards, and which ones, are still good leads, i.e. generate more than 50%?

If 6 out of 9 are still good, was the prediction valid? How about 7 out of 9, or 8/9 or 9/9. How many cards have to be better than 50% for the prediction to be valid?

9 = 50.7% (24)

10 = 55.2% (6)

9 = 50.1% (28)

J = 52.6% (15)

Q = 50.3% (27)

A = 54.3% (8)

3 = 53.0% (12)

10 = 44.5% (52)

A = 55.3% (5)

With one exception, Hammond Leads are working. I'm going to add it to my convention card. 8 out of the 9 cards still generate matchpoint percentages greater than 50%. I think I need to drop the 10 from the list.

Conclusions.

Look at the conclusions from SWITBOL. All still true.

1. If you have it, lead a black nine. (scores above 50%)

2. Never lead a red eight. Remember: BANNER - Black Always Nine, Never Eight Red. Unless you are playing against me.

3. Black fives should be avoided. Still true, 5 (46) 46.5%, 5 (29) 49.6%.

4. If you have to lead an Ace, lead a red one - they do much better than the black ones. Still true. Orlando results: A (8) 54.3%, A (5) 55.3%, A (17) 52.5% A (26) 50.4%.

5. 8 is the safest lead. I don't have the hand record data from WBF, but the 8 is currently the best lead for Orlando. Scores the highest percentage score.

In summary, SWITBOL was accurate in its predictions and what to lead.

Before you post anything, please read and re-read Point 1 from SWITBOL (it's on page 9).

I do write about statistics and bridge. Some of them are serious, some not so. This article is 100% guaranteed to be in one of those two categories.

Publishing this data may taint future results.

23 Comments
Getting Comments... loading...
.

Bottom Home Top