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Šibenik Backgammon Quiz 2014. - SOLUTIONS

Posted By: Mislav Kovacic
Date: Sunday, 21 September 2014, at 2:01 a.m.

In Response To: Šibenik Backgammon Quiz 2014. (Mislav Kovacic)

Thanks for showing interest in my quiz. Here are the solutions and the brief explanation of all positions. Unfortunately, my computer is on repair at the moment so I can't provide you with the XG IDs and equities, but in almost all of the positions the correct move is ahead by pretty large margin (usually more than 0.080-0.100)

PROBLEM 1
Correct is c) 13/7* 11/7.
24/14* gives the opponent too many anchor-making entries and 13/7* 6/2* is just too aggressive, you overshoot your market when the opponent dances (or enters with just 1 checker) and his 2s hurt you. No need to give him any counterplay, 13/7* 11/7 improves your attacking and priming potential (especially since he has a 2pt made) giving you some nasty (and more efficient) cubes in the future. It basically leaves Black without any real counter chances.

PROBLEM 2
Correct is c) 22/18* 18/16
Hitting is pretty basic and after that 18/16 minimzes opponent's return shots and it also makes some of his entering 6s really awkward. (16, 26, 46, 56)

PROBLEM 3
Correct is d) 11/5 6/5
White is trailing by 1 pip after the roll so running makes no sense. Also, the opponent has 2 checkers out of play which usually makes you want to maximize contact because you are playing with 15-man army against the 13-man one. White's back checker does a nice job of guarding against Black's many homeboard slotting plays.
As is most often the case, making 5pt beats making 7pt by a pretty large margin. You are only leaving 54 and 64 (which already plays well for Black) and it's a ''risk'' worth taking to make the best offensive point.

PROBLEM 4
Correct is a) Bar/20 24/20
This one is a good example why we should never be on auto-pilot. Many got it wrong and I can understand why. Figthing for the high points in your homeboard is often correct in the early game but here it's just fruitless. After Bar/20 9/5* Black hits you with almost all entering 5s and 4s, and on the other side of the board he loose hits you with 1s, 2s and 3s. With 11 checkers in the offense it's time to button up and just make the anchor. It leaves him the double shot (note that 4s already play well for him) but with the golden anchor made there is really nothing to be afraid of.

PROBLEM 5
Correct is d) 22/17 3/2
Many people hit here, but it's a pretty big blunder. After the hit, White needs to roll 2, 5 and 5 again and he needs to do it pretty soon. This is much harder than it looks and White is running a risk of having his checker(s) stuck back and having to destroy his front position. If you like the hit here I suggest playing out the position after 15/9* multiple times against the bot. Coming out is a must, and after that the cool-looking 3/2 diversifies White's numbers, so that he can cover with the 1s and move his back checker with the 2s.

PROBLEM 6
Correct is c) Bar/23* 8/7
Only 13% of the people got this one correct. Due to an awkward 1, many were attracted by Bar/24 6/4 but it's a huge blunder giving your opponent full roll and tons of rolls to either point on your head or hit you loose. If you are afraid to hit, simply note that when you hit you at least make Black dance 25% of the time in the next roll and when he does enter he only has half a roll left. So hitting is a must and after that it's just matter of minimizing Black's return shots.
9/8 leaves 14, 34, 54, 36 as return shots (8 combinations), while 8/7 leaves only 13, 33 and 53 (5 combinations) making it a winner.

PROBLEM 7
Correct is a) 22/18 21/18
Only 16% got this one correct. 8/4* 7/4 is strong IF Black dances because you can cash. But 75% of the time he enters and you are left in a prime vs prime position where your back checkers are far from being comfortable and Black has some definite counter chances. After 22/18 21/18 White is ahead by 16 pips and Black is under tremendous pressure due to 2 blots and no anchor.

PROBLEM 8
Correct is e) 9/3 7/6
This move allows White to bearoff in the next roll with 66, 55, 44, 33 and 22, more than any of the alternatives. It surprised me that many got this one wrong as well.

PROBLEM 9
Correct is e) Bar/24 /24/22
When you are playing backgame you want good timing and a prime so that when you hit the opponent's checker it gets stuck back for as long as possible. Here White has a solid timing but he is seriously undeveloped. As much as you would want to hit, at this particular moment it doesn't accomplish anything. Black is under no serious pressure, and the only thing the hit does is - it gives your opponent 23 free pips to improve his timing. This equates to nearly 3 more rolls for you to potentially ruin your front position by rolling big.

PROBLEM 10
Correct is c) Double / Pass
Only 16% of the people got this right. If the pip count was available, this % might have been a bit higher.
Here it's essential to note that White is leading by 20 pips. He also has a stronger homeboard, an anchor and the numerous threats, the most obvious being hitting Black's blot. So if you are looking at Race-Position-Threats factors white's position is just crushing in all regards and black has nothing going for him. This is a pretty solid pass, and not that far from being a TG. Almost everyone took it.

PROBLEM 11
Correct is a) No Double / Take.
White's position is again better in many ways but the anchor gives black tons of counterplay making this a pretty solid No Double. White has almost no way to easily lose the market here. The only variations I see at the moment are White rolling 55 or 66 and black dancing with BOTH of his checkers. Even after 53 – dance, or 55 – 1 enters it's still a pretty solid take.
40% of the participants thought it was a pass so that probably makes this a good bluffing position against the right opponent.

PROBLEM 12
Correct is b) Double / Take
White hits 75% of the time and he wins almost all of these games. Not all of them due to Black's 1 checker off. When White misses Black just cashes. Since Black has 25%+ in the position it's an easy take for him.

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