Master's Panel 3—Updated
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From Backgammon Times, Volume 3, Number 2, Summer 1983.
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Mike Senkiewicz recently discovered some old issues of Backgammon News, a newsletter published by Prince Alexis Obolensky's World Backgammon Club in the early 1970s. In each issue Obolensky ran a Master's Panel where several leading players tackled a series of interesting problems.
With Backgammon News Editor Joe Pasternack's permission, we have reprinted a set of Master's Panel problems along with the answers of the old Masters. To make things interesting we have put the problems to a panel of current Masters hand-picked by Senkiewicz.
This is the third in the series. See how you handle the positions and see if the Masters agree.
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Problem 1
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White to play 5-3.
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Old Masters
| P. Bauer-Mengelberg |
Strong opponent cover, weak opponent hit. |
| Claude Beer |
Make 5 point. |
| Mike Carson |
Make 5 point. |
| Ralph Chafetz |
Make 5 point. |
| Lewis Deyong |
Make 5 point. |
| Porter Ijams |
Make 5 point. |
| Alexis Obolensky |
Make 5 point. |
| Mr. and Mrs. Jacoby |
Make 5 point. |
| Tobias Stone |
Make 5 point. |
New Masters
| Kit Woosley |
13/5. Making the 5-point guarantees the superior positions even if Black counters with a point of his own, for White is then on roll with slightly better distribution, and if Black fails to make a point White will have much the better of it. If White hits and gets hit back, he has nothing. |
| Bill Robertie |
13/5. Clear. Only a hopeless player would consider the hit. |
| Kent Goulding |
Make the 5-point. The "strong opponent cover, weak opponent hit" idea was valid ten years ago, but today no player is that weak. |
| Sandy Lubetkin |
Make 5 point. |
| Nack Ballard |
Make the 5-point. Estimated equity advantage after making the 5-point = +0.2; estimated equity advantage after hitting Black = +0.15. |
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Problem 2
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Black to play 4-4.
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Old Masters
| P. Bauer-Mengelberg |
24/16(2). |
| Claude Beer |
24/16, 13/5. |
| Mike Carson |
24/16, 11/3. |
| Ralph Chafetz |
24/16, 13/9(2). |
| Lewis Deyong |
24/16, 13/9(2). |
| Porter Ijams |
24/16, 13/5. |
| Alexis Obolensky |
24/16, 13/9(2). |
| Mr. and Mrs. Jacoby |
24/16(2). |
| Tobias Stone |
24/16, 13/9(2). |
New Masters
| Kit Woosley |
13/9(2), 24/16. The 9-point should have some value, and Black covers his blot, keeps outfield control, and starts the men on the 24-point moving. The alternative of making the 5-point gives White too much freedom in the outfield and leaves the mess on the 24-point; this is too great a price to pay even for making the 5-point. |
| Bill Robertie |
13/5(2). Black can always fool around in the outfield later on. For now he should try to improve his position in the most direct way possible. |
| Kent Goulding |
Make the 5-point. It's tempting to make both 9 points, but my strict upbringing forces me to make both 5 points instead. |
| Sandy Lubetkin |
24/16, make 9 point. Best chance for a quick win without jeopardizing overall game. |
| Nack Ballard |
Make the 5-point. Although it risks losing outfield control and getting stuck with an ace-five game, making the 5-point puts maximum pressure on White and threatens a quick win on a follow-up hit. |
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Problem 3
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Black to play 6-1.
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Old Masters
| P. Bauer-Mengelberg |
24/17. |
| Claude Beer |
24/17. |
| Mike Carson |
23/17, 6/5. |
| Ralph Chafetz |
24/17. |
| Lewis Deyong |
Order a scotch—a double. |
| Porter Ijams |
24/17. |
| Alexis Obolensky |
24/17. |
| Mr. and Mrs. Jacoby |
24/23, 13/7. |
| Tobias Stone |
24/17. |
New Masters
| Kit Woosley |
24/17. Black's only asset is his outfield control, and he must play to build on that advantage. Black will plan to make the 23-point and eventually win a priming or hitting contest, with a 2-point game in reserve. The various hitting plays try to do too much with too little ammunition, and if they don't work Black is left with 3 men stuck forever on the 24-point. |
| Bill Robertie |
24/17. Actually, this is a pretty good roll, considering how bad the position is. |
| Kent Goulding |
23/16*. The "backgame" is hopeless. Hit White's blot (leaving his blockade completely stripped) and hope to force him to break. |
| Sandy Lubetkin |
24/17. Most flexible. |
| Nack Ballard |
24/17. Retains almost as many forward winning tries as hitting on the 16-point (23/16*) or hitting on Black's 5 point (23/17, 6/5*) while decreasing gammon chances and maintaining better timing on the undesirable but playable ace-point, deuce-point, or ace-deuce games. |
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Problem 4
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Black to play 3-1.
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Old Masters
| P. Bauer-Mengelberg |
9/5. |
| Claude Beer |
9/6, 13/12. |
| Mike Carson |
5/2, 13/12. |
| Ralph Chafetz |
6/2. |
| Lewis Deyong |
6/2. |
| Porter Ijams |
9/6, 13/12. |
| Alexis Obolensky |
9/6, 13/12. |
| Mr. and Mrs. Jacoby |
9/6, 13/12. |
| Tobias Stone |
9/6, 13/12. |
New Masters
| Kit Woosley |
9/6, 13/12. Calculations show that splitting to the 12-point is by far the most likely way to hit a shot, which is Black's primary goal. The alternative of 13/12, 5/2 is the only close choice, but the loss on 1-1, 2-1, 2-3, and 2-4 outweighs the gain on 2-5 and 2-6. |
| Bill Robertie |
9/6, 13/12. Black is about 50% more likely to hit after this play than after 9/5, and he must hit to win. |
| Kent Goulding |
13/12, 9/6. I wouldn't leave three blots in the outfield. Also, keeping the midpoint doesn't appear to get as many shots. |
| Sandy Lubetkin |
9/6, 13/12. Checker on the 9 point is a liability there (e.g., 2-1, 1-1, and 2-2 hit) and gains almost nothing. |
| Nack Ballard |
13/12, 5/2. 13/12, 9/6 yields 285/1296 hits and moderate repeat chances; 5/2, 5/4 yields 201/1296 hits and some moderate repeat chances; 9/5 yields 197/1296 hits and almost no repeat chances; and 13/12, 5/2 yields 290/1296 hits and reasonable repeat chances! (The slight increased gammon vig is too small to matter.)
What makes 13/12, 5/2 and 13/12, 9/6 so close is the superior board of the latter play (also slight racing benefit). 5/1296 would not normally be quite enough to cover this difference; however, 13/12, 5/2 also yields repeat hit chances 15/36 of the time; 13/12, 9/6 only 9/36 of White's rolls. |
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Problem 5
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White to play 5-4.
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Old Masters
| P. Bauer-Mengelberg |
Bar/20, 13/9*. |
| Claude Beer |
Bar/20, 24/20. |
| Mike Carson |
Bar/20, 13/9*. |
| Ralph Chafetz |
Bar/20, 13/9*. |
| Lewis Deyong |
Bar/20, 24/20. |
| Porter Ijams |
Bar/20, 24/20. |
| Alexis Obolensky |
Bar/20, 13/9*. |
| Mr. and Mrs. Jacoby |
Bar/20, 13/9*. |
| Tobias Stone |
Bar/20, 13/9*. |
New Masters
| Kit Woosley |
Bar/20, 13/9*. White's back men are in no great danger, so making the 20-point is not urgent. It is more important to stop Black from playing with one man back and to get to work on White's board, and hitting is superior on both these counts. |
| Bill Robertie |
Bar/20, 13/9*. Too soon to button up. |
| Kent Goulding |
Bar/20, 13/9*. Making the 20-point is clearly inferior. (In fact, bar/21, 13/8 is probably the second best play!) |
| Sandy Lubetkin |
Hit on 9 point. |
| Nack Ballard |
Bar/20, 13/9*. Clearly the best. |
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Problem 6
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Black doubles.
Should White take?
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Old Masters
| P. Bauer-Mengelberg |
Take if losing. |
| Claude Beer |
Take. |
| Mike Carson |
Pass. |
| Ralph Chafetz |
Pass. |
| Lewis Deyong |
Take. |
| Porter Ijams |
Pass. |
| Alexis Obolensky |
Pass. |
| Mr. and Mrs. Jacoby |
Pass. |
| Tobias Stone |
Take. |
New Masters
| Kit Woosley |
Take, though it turned out surprisingly close when I rolled it out. The problem is that when White loses he almost always gets gammoned. However, White claims or virtually claims on the 7 rolls that Black misses, plus White has some fighting chances even if he is hit, and these possibilities put his winning chances at about the 50% mark, enough to justify a take despite the grave gammon dangers. |
| Bill Robertie |
Take. The take is so easy that the position may not even be a correct double. I would only turn the cube as Black because many players would pass. |
| Kent Goulding |
Take. I haven't played it out, but I'd be surprised if this is even close. |
| Sandy Lubetkin |
Take. Win enough even if gammoned 30% of the time. |
| Nack Ballard |
Beaver. (Proposition anyone?) You may rate to get gammoned three or four times as often as your opponent, but I beaver! |
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Problem 7
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Black doubles.
Should White take?
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Old Masters
| P. Bauer-Mengelberg |
Beaver. |
| Claude Beer |
Take. |
| Mike Carson |
Take. |
| Ralph Chafetz |
Take. |
| Lewis Deyong |
Take. |
| Porter Ijams |
Pass. |
| Alexis Obolensky |
Pass. |
| Mr. and Mrs. Jacoby |
Mr. J. takes; Mrs. J. passes. |
| Tobias Stone |
Pass. |
New Masters
| Kit Woosley |
Trivial take. Wouldn't surprise me if it were a beaver. White is well ahead in the race, doesn't have to leave a shot, and Black doesn't have to hit a shot if it is left. Also, if White can survive the next couple of rolls Black can't hold everything. The gammon risk isn't as great as it seems, for White probably won't have to leave more than one blot at a time and Black doesn't have the ammunition for a closeout. I started rolling it out. White won the first seven games, so this seemed totally convincing that it is a take. Black should at least wait for a shot to consider doubling in this type of position, unless he believes there is a significant chance that his opponent will pass. |
| Bill Robertie |
Take. Again, a very easy take and probably not a theoretically correct double. |
| Kent Goulding |
Take. If you play beavers, give it serious consideration. Black should not have doubled. |
| Sandy Lubetkin |
Take. |
| Nack Ballard |
Easy take, almost a beaver. What clarifies the theoretical prematurity of the double is that the few market-losing sequences that exist involve relatively small savings. However, if I think there is only a one-in-eight chance my opponent will pass, I happily spin! |
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Continue to Master's Panel Updated #4.
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