Part 3: The 6-point is cleared - smooth position

from: Marc Werner and Christian Liebe-Harkort

In this chapter we will analyze a posiotion, where you have already cleared the 6-point.

Part 3  differs greatly from position part 1 and 2. Black has successfully cleared his 6 point and has beard two checkers off, leaving him with a 5(3), 4(3), 3(4), 3(2) formation on his remaining points.

Position 809, Category Anchor

Black to play 6 1

Black vs White

Moneygame: Jacoby and Beaver

added at 4/8/2010 6:14 PM, from dongbang

Pipcount: 45(-115) - 160(+115)

Comment:
The right play is still 5/off, 4/3 stripping the two highest points and leaving two horror shakes the next turn 6-4 and 5-4, producing two blots for black; 4-3 and 3-3 leaves a single blot-a total of seven bad shakes the next turn. The alternative 3/2 leaves 6-4, 5-4, 6-6, 5-5, 4-4, 3-3-a total of seven bad shakes the next turn.
Note: After 5/off, 4/3 black will get hit: 102 (2x11+2x20+2x20 shots) / 1296 = 7,87% in a cross section of 1296 (36x 36).

1) 5/0ff 4/3
Equity: +1.274 7 ply

Player: 80.30%17.65%51.24%11.41%
Opponent: 19.70%19.70%0.00%0.00%

Pipcount: 39(-121) - 160(+121)

2) 5/0ff 3/2
Equity: +1.246 (-0.028) 7 ply

Player: 79.56%17.60%51.15%10.81%
Opponent: 20.44%20.44%0.00%0.00%

3) 5/4 5/0ff
Equity: +0.821 (-0.453) XG Roller+

Player: 67.02%17.29%40.26%9.47%
Opponent: 32.98%32.98%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Position 810, Category Anchor

Black to play 3 1

Black vs White

Moneygame: Jacoby and Beaver

added at 4/8/2010 6:24 PM, from dongbang

Pipcount: 45(-115) - 160(+115)

Comment:
Not surprisingly, by far the best move here is 5/4, 3/off being even on the two highest points and paying only to 6-4, 5-4 and 3-3 next roll.
Note: After 5/4, 3/off black will get hit: 55 (1x11 + 2x11+2x11 shots) / 1296 = 4,24% in a cross section of 1296 (36x 36).

1) 5/4 3/0ff
Equity: +1.331 7 ply

Player: 81.80%18.28%51.19%12.33%
Opponent: 18.20%18.20%0.00%0.00%

Pipcount: 41(-119) - 160(+119)

2) 5/2 4/3
Equity: +1.208 (-0.123) 7 ply

Player: 79.02%18.02%51.38%9.62%
Opponent: 20.98%20.98%0.00%0.00%

3) 4/0ff
Equity: +1.163 (-0.168) XG Roller+

Player: 77.21%18.17%48.25%10.79%
Opponent: 22.79%22.79%0.00%0.00%

4) 5/2 3/2
Equity: +1.162 (-0.169) 7 ply

Player: 77.70%17.89%50.74%9.07%
Opponent: 22.30%22.30%0.00%0.00%

5) 3/2 3/0ff
Equity: +1.118 (-0.213) XG Roller+

Player: 76.11%17.71%48.58%9.82%
Opponent: 23.89%23.89%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Position 811, Category Anchor

Black to play 2 1

Black vs White

Moneygame: Jacoby and Beaver

added at 4/8/2010 6:28 PM, from dongbang

Pipcount: 45(-115) - 160(+115)

Comment:
Top choice is 5/4, 2/off.Again being even on the two highest points, again leaving only 6-4 and 5-4 as bad rolls the next turn.
Note: Playing 3/off in this position is close to a blunder.

1) 5/4 2/0ff
Equity: +1.372 7 ply

Player: 82.79%18.46%51.08%13.25%
Opponent: 17.21%17.21%0.00%0.00%

Pipcount: 42(-118) - 160(+118)

2) 3/0ff
Equity: +1.282 (-0.090) 7 ply

Player: 80.51%18.65%49.70%12.16%
Opponent: 19.49%19.49%0.00%0.00%

3) 5/3 4/3
Equity: +1.260 (-0.112) XG Roller+

Player: 80.17%18.14%51.04%10.99%
Opponent: 19.83%19.83%0.00%0.00%

4) 5/2
Equity: +1.259 (-0.113) XG Roller+

Player: 80.27%17.92%52.04%10.31%
Opponent: 19.73%19.73%0.00%0.00%

5) 4/3 2/0ff
Equity: +1.107 (-0.265) XG Roller+

Player: 75.59%18.57%45.71%11.31%
Opponent: 24.41%24.41%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Position 812, Category Anchor

Black to play 5 2

Black vs White

Moneygame: Jacoby and Beaver

added at 4/8/2010 6:31 PM, from dongbang

Pipcount: 45(-115) - 160(+115)

Comment:
Bearing off two checkers with 5/off, 2/off is clearly best. Seemingly inferior is 5/off, 4/2 stripping the 5- and 4 point here and leaving two horror shakes on the next turn (6-4 and 5-4) which will produce two blots for black and 4-3 leaving a single blot.
Note: After 5/off, 4/2 black will get hit: 102 (2x20+2x20+2x11 shots) / 1296 = 7,87% in a cross section of 1296 (36x 36).

1) 5/0ff 2/0ff
Equity: +1.310 7 ply

Player: 80.84%18.35%49.02%13.47%
Opponent: 19.16%19.16%0.00%0.00%

Pipcount: 38(-122) - 160(+122)

2) 5/0ff 4/2
Equity: +1.245 (-0.065) 7 ply

Player: 79.51%16.92%52.06%10.53%
Opponent: 20.49%20.49%0.00%0.00%

3) 5/3 5/0ff
Equity: +0.875 (-0.435) XG Roller+

Player: 68.36%16.63%42.09%9.64%
Opponent: 31.64%31.64%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Position 813, Category Anchor

Black to play 3 2

Black vs White

Moneygame: Jacoby and Beaver

added at 4/8/2010 6:37 PM, from dongbang

Pipcount: 45(-115) - 160(+115)

Comment:
Simply bearing off one checker or bearing off two checkers with 3/off, 2/off (a matter of taste between these two moves) is the best move here. Again playing 5/4, 4/2 (leaving the same stripped position as in # 812) is a big blunder.
Note: After 5/off black will get hit 66 (1x11+1x11+2x11+2x11 shots) / 1296 = 5,09% in a cross section of 1296 (36x 36)
After 3/off, 2/off black will get hit only 22 (2x11 shots) / 1296 = 1,69%

1) 5/0ff
Equity: +1.319 7 ply

Player: 81.47%18.10%51.26%12.11%
Opponent: 18.53%18.53%0.00%0.00%

Pipcount: 40(-120) - 160(+120)

2) 3/0ff 2/0ff
Equity: +1.310 (-0.009) 7 ply

Player: 80.94%18.66%48.77%13.51%
Opponent: 19.06%19.06%0.00%0.00%

3) 5/2 4/2
Equity: +1.165 (-0.154) 7 ply

Player: 77.86%17.51%51.60%8.75%
Opponent: 22.14%22.14%0.00%0.00%

4) 4/2 3/0ff
Equity: +1.105 (-0.214) XG Roller+

Player: 75.65%17.27%48.61%9.77%
Opponent: 24.35%24.35%0.00%0.00%

5) 5/3 5/2
Equity: +0.787 (-0.532) XG Roller+

Player: 66.49%16.17%41.95%8.37%
Opponent: 33.51%33.51%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Position 824, Category Anchor

Black to play 1 1

Black vs White

Moneygame: Jacoby and Beaver

added at 4/11/2010 10:19 AM, from admin

Pipcount: 45(-115) - 160(+115)

Comment:
The first 3 aces are easy: you have to clear the 5 point. The last ace is best to smooth 4/3, even this leaves ann odd number of checkers on the highest point.

1) 5/4(2) 5/3
Equity: +1.396 7 ply

Player: 83.74%18.33%53.07%12.34%
Opponent: 16.26%16.26%0.00%0.00%

Pipcount: 41(-119) - 160(+119)

2) 5/4(3) 3/2
Equity: +1.358 (-0.038) 7 ply

Player: 82.78%18.56%52.28%11.94%
Opponent: 17.22%17.22%0.00%0.00%

3) 5/2 4/3
Equity: +1.206 (-0.190) XG Roller+

Player: 78.62%17.36%51.35%9.91%
Opponent: 21.38%21.38%0.00%0.00%

4) 4/3(2) 4/2
Equity: +1.204 (-0.192) 1 ply

Player: 79.34%18.29%53.33%7.72%
Opponent: 20.66%20.66%0.00%0.00%

5) 5/2 3/2
Equity: +1.174 (-0.222) XG Roller+

Player: 77.89%17.40%51.28%9.21%
Opponent: 22.11%22.11%0.00%0.00%

Software: eXtreme Gammon Version: 1.13

Things are a little bit different now compared to part 1 and 2. Only with the 6-1 now it is right to strip the two highest points (5-and 4 point), leaving the 5 (2), 4 (2), 3 (5) formation on the three highest points which seems very slightly better than the 5(2), 4(3), 3(3) formation now. With the other rolls containing an ace it is better to reach the 5(2), 4(4) formation on the two highest points after which black has only two bad numbers, the 6-4 and 5-4, leaving only one blot. With the 5 and 4 point stripped in this position black has always two double blotting numbers, the 6-4 and the 5-4 exposing both two blots. With the rolls of 3-2 and 5-2 it is best to strip only the 5 point, leaving the 5(2), 4(3) formation on the two highest points and bear off one checker. In case of the 3-2 it makes practically no difference between this and bearing off two checkers and leaving the 5(3), 4(3), 3(3) formation, which also looks good and safe.

updated: Thursday, April 15, 2010