| |
BGonline.org Forums
Othello Quiz 2017
Posted By: Michael In Response To: Othello Quiz 2017 (othello)
Date: Monday, 8 May 2017, at 9:53 a.m.
PROBLEM 7
*********
If we play 8/5 she fails to get in 19/36, we hit about 1:3 so our saving the gammon chances without hitting are about 16%.
If she makes it to get in, our pips out of board will be 57, with average pips per rol 8.2 we need 6.95 rolls with full effectiveness say 9 rolls with not so full effectiveness including half a roll to bear off one checker.However she would normally finish in 8 rolls!! It looks if we don't hit we are losing a gammon (and the match) most of the times.
So primary goal is to try saving the gammon by hitting with 13/12*
More problems now, how to play the 2.
To save the gammon, all we need is a few rolls without getting hit.
a)13/11 is too risky because even if she wont hit from bar,we would have problems getting 3 checkers safe plus making our 5 point. Many of our rolls on next exchange leave about 7 shots.
b)12/10 is less risky but less effective in making the 5 point plus adds 46 to her hitting from bar rolls.
I conclude we have to leave the minimum number of shots, and if she hits maximize the possibility to hit her later.
13/12* 5/3.
NB. Too much work in counting rolls, and shots, and stuff in depth of 2-3
PROBLEM 8
**********
Another very difficult one where I had to count a million rolls, and shots and stuff.
Here the obvious parameter is the gammon go Vs loss of single wins. Notice there are 2 ways to win a gammon.Hit right now followed by a quick closeup (rather difficult) and the second way hit another checker on next exchange.
a)13/9 5/2 :11/36 (22,23,24,25,45 possibly 26) risks the single wins
2/36 (46) Runs keeping gammon go alive.
b)13/6: O doesn't have much to play.
10/36 :direct shots aiming at a 2nd checker on bar if she hits loose with most of her aces (12,13,14,15,16).
9/36: Some return shots aiming at a 2nd checker on bar (23,24,33,34,56 )
6/36: Runs leaving a direct shot on existing blot (52,53,54)
1/36: Runs leaving no return shots (55)
2/36: Leaves a Direct shot on 2nd checker (46)
In total I would say 18/36 of her rolls still keep the gammon go option alive without risking our single wins by much.
The gammon value for X Ats is 0.81. The question is does risking 11/36 Single Wins worth it considering we would still have about 18/36 of her rolls still keep the gammon go option alive? "Risking" and "losing" , "having" and "winning" are of course different words. But I have no other way to compare the 2 results.
The tradeoff based on the gammon values delivers it's worth to risk 8.91 single wins. We obviously risk more by hitting.
13/6
| |
BGonline.org Forums is maintained by Stick with WebBBS 5.12.