[Wackojack]

Quote “Nobody likes to be proven wrong.
If the facts do not support their assessment, they will rather question the facts (or claim they are not "relevant") than change their minds” Unquote

Your 2nd study that found NS made on average 1.1 more tricks than EW has only 900 deals for NS and 1000 deals for EW.

Your 1st study listed 1000 deals each way and found that NS made on average 1.0 more tricks than EW.

I for one am very happy to reconsider my opinion which assumed that NS would make somewhat less than one trick more than NS. Conventional wisdom is not always correct. Could I therefore ask that the results be presented as follows or at least in an improved way:

Of the number of deals that West can make x tricks:
How many times does South make x tricks or fewer? This would favour pass in MP
How many times does South make x+1 tricks or more? This would favour open 1♥.in MP
The results would need to be imped in a team match and the game bonus would therefore skew the tipping point to favour NS.

What interests me now is how do we indentify these hands that should be opened in 4th position? We do not have the luxury of doing a simulation study at the table. So back to basics:
With North having 5 hearts and a singleton spade, on average NS will have 7 and 2/3 hearts and EW 8 spades. Then according to the LAW the median total tricks = 15 and 2/3. And if NS and EW have equal strength and other things being equal you would expect on average EW to have the advantage in trick taking. On average however, NS will have a strength advantage. NS will have 20 and 2/3 HCP and EW 19 and 1/3, giving NS an average advantage of 1 and 1/3 HCP. What fraction of a trick in favour of NS would this represent? Perhaps this would even up the average trick taking potential.

Then why do the studies show an average of 1 more trick for NS? One thing that was mentioned is that a bad spade break for EW is assured whereas a bad heart break for NS is probabilistic. Also South having A and AQ put NS ahead in trick taking potential and damaging EW’s trick taking potential. Could this be responsible for the extra trick?

[rhm]

Wackojack, on 2016-May-01, 02:51, said:

What interests me now is how do we indentify these hands that should be opened in 4th position? We do not have the luxury of doing a simulation study at the table. So back to basics:

Quite right.
I did not do the simulation and then came to a conclusion, but because my assessment of the South did not coincide with the vast majority of posters, I checked my assessment of the South hand with simulations.
I am not a slave to HCP or rules of thumb like Pearson points, though I do take them into account, if I am in doubt.
In my experience most players are.

What I do not do is passing a hand in fourth position I would open in any other.

Quote

Then why do the studies show an average of 1 more trick for NS?
One thing that was mentioned is that a bad spade break for EW is assured whereas a bad heart break for NS is probabilistic. Also South having A and AQ put NS ahead in trick taking potential and damaging EW’s trick taking potential. Could this be responsible for the extra trick?

To answer your question:

Learn to evaluate hands properly. Sims can help develop good hand evaluation.

For example understand that the combination of a preponderance of aces and good distribution and length in a major is a reason for upgrades not for downgrades.
You will need to find a fit, in notrump the hand is worth less.
This is what gives us more playing power than East West and better chances of additional defensive tricks.
Location of honors can be a detriment but is much less important than people think and should take a backseat. That is the reason why even K&R is plain wrong on this hand.

Rainer Herrmann

[rhm]

Wackojack, on 2016-May-01, 02:51, said:

Quote “Nobody likes to be proven wrong.

Of the number of deals that West can make x tricks:
How many times does South make x tricks or fewer? This would favour pass in MP
How many times does South make x+1 tricks or more? This would favour open 1♥.in MP
The results would need to be imped in a team match and the game bonus would therefore skew the tipping point to favour NS.

I use Dealmaster Pro for simulation, which has strength and weaknesses.
The problem with your question is, that the number of tricks South makes, depends where a fit exists.
West and East are unlikely to compete successfully unless they have a spade fit.
But North South could have a fit in any other suit.
If North South have an advantage on average of more than 0.5 tricks they will be able to outbid East-West on the majority of deals.
Having an advantage of one trick or more means there are very few deals where East West can outbid North South.
If East West got a spade fit and North South will have no heart fit, it is extremely likely they have a fit in a minor.
In fact there is just one specific distribution for North 4♠=2♥=4♦=3♣, where East West have an 8 card spade fit and we have no fit.
I checked what would happen if North would have at most 4 spades, at most 2 hearts and four or more clubs (at most six).
In this case they have a spade fit, and we have a club fit.
Of course game is unlikely since we now need 11 tricks. But I expected we can still outbid East West. The results more than confirmed my expectations. The difference in trick taking is now even larger. South spade ruffs will now be in "shorter" trump hand.

1000 random deals

Result:

South made on average per deal 9.3 tricks with clubs as trumps
West made on average per deal 7.5 tricks with spades as trumps

The breakdown of tricks in clubs for South was as follows:

>7 7 - 8 -- 9 -- 10 - 11 12 13 tricks
7 42 195 315 282 116 40 3 deals

The breakdown of tricks in spades for West was as follows:

>7 -- 7 -- 8 --- 9 - 10 11 12 tricks
208 324 278 155 32 3 0 deals

Note, North South are much more likely to make game in clubs, about one deal in six , than East West in spades, about one in 30.

Rainer Herrmann

[Zelandakh]

rhm, on 2016-May-01, 07:41, said:

I checked what would happen if

Why not simply do a simulation based on what is known (3 passes and the South hand) rather than specifying various scenarios that may or may not reflect the overall situation? Perhaps one of our other sim-gurus would be willing to program that if Rainer remains reluctant.

[gwnn]

I would open the hand 1H in 4th seat with or without the simulations (this is more of a case of "a broken clock is right twice a day" than anything else as I open just about every hand in 4th seat). I do find them interesting in this case, particularly how big the difference in expected number of tricks is.

But could you just do the unrestricted simulation? I understand that it is easier to compare the tricks in specific strains as opposed to the tricks in the best fit whatever they may be, but maybe it would be interesting to see the likelihoods of various scenarios without any constraints on distributions, except maybe <6 spades and <7 minors for all three other players to account for their lack of preempts (and of course <12 points or <11 points).

edit: cross-posted with Zel above.

This post has been edited by gwnn: 2016-May-01, 09:16

[rhm]

Zelandakh, on 2016-May-01, 09:10, said:

Why not simply do a simulation based on what is known (3 passes and the South hand) rather than specifying various scenarios that may or may not reflect the overall situation? Perhaps one of our other sim-gurus would be willing to program that if Rainer remains reluctant.

I have done this but then I have to count manually the deals where East West can make as many or more tricks in spades than North South in any of the other trump strains.
The result is about 20% and around 80% where North South can make in at least one trump suit more tricks, often in two trump suits.

Rainer Herrmann

[Wackojack]

Rainer:

In the light of your studies and most of the points you have made, I am tipping towards the view that opening 1♥ on the South hand is the odds on winner. Thank you for that.

Now you say this:

Quote "What I do not do is passing a hand in fourth position I would open in any other" Unquote.

Are you serious? I am hoping that you didnt really mean what you were saying. ♠xx, ♥KQxx, ♦Kxxx, ♣KJx. Would you open this hand in 4th position OR would you not open this in other positions?

[gwnn]

Quote

♠xx, ♥KQxx, ♦Kxxx, ♣KJx

Unless my partner were known to be a light opener or my RHO were known not to be able to open in 3rd seat with suitably reduced strength, I'd open that hand too. We have a 12 count and nobody else at the table has a 12 count. Moreover, RHO has a lower minimum than my partner so we're already outgunning them by quite a margin. The only real problem case is if LHO has precisely 5 spades (with 6 he would likely have opened already, and RHO would have opened 1S on most hands with his likely strength and 5 spades). A 4-4 spade fit is possible too of course but in that case they still need to find it.

[rhm]

Wackojack, on 2016-May-01, 09:34, said:

Are you serious? I am hoping that you didnt really mean what you were saying. ♠xx, ♥KQxx, ♦Kxxx, ♣KJx. Would you open this hand in 4th position OR would you not open this in other positions?

I would not mind passing this hand in any position.
I would certainly pass in second position and in first if vulnerable.
I like to open light on unbalanced hands and aces are important.
Balanced ace less hands are overrated.
Make it any stronger and I open.

Rainer Herrmann

[Zelandakh]

rhm, on 2016-May-01, 09:26, said:

I have done this but then I have to count manually the deals where East West can make as many or more tricks in spades than North South in any of the other trump strains.

How about calculating the IMP expectation based on the par score without doubles? There are some good reasons why this is perhaps unrealistic but it strikes me as one way of providing an objective number rather than continuing to make assumptions about where the hand might be played. It is comparatively quick and easy to calculate so I cannot see any reason not to do so. We can argue about the significance of the result once it is available (note that I am neutral in that discussion having no position to defend).

[mikestar13]

manudude03, on 2016-March-14, 17:57, said:

I would pass, but think it's close. I would have been very surprised to find we were missing game though.

Also, singleton aces are not really good. In fact, if anything, it's something to downgrade.

That's overdoing it a bit, IMHO: the singleton ace gets a downgrade for inflexibility, but still gets the upgrade for being an ace. These two factors approximately cancel.