[ View Thread ] [ Post Response ] [ Return to Index ] [ Read Prev Msg ] [ Read Next Msg ]

BGonline.org Forums

Late bear off races - amazing discovery

Posted By: Ray Kershaw
Date: Saturday, 2 February 2013, at 8:43 p.m.

A chapter in my book Backgammon Funfair (www.backgammonfunfair.com, available in Europe from me and in the USA and elsewhere from Carol Joy Cole) describes a few cube provocation plays which were analysed three decades ago by Danny Kleinman.

A cube provocation play is a correct checker play after which your opponent should double or redouble, when you have at least one wrong checker play after which your opponent should not double or redouble.

Jeroen Sikkema has made the amazing discovery that there are hundreds, perhaps thousands, of cube provocation plays in late bear off races. (So this has nothing to do with gammons.)

Here are three examples from Jeroen's list:

Correct play is 6/off, 3/1 after which White should redouble. Wrong play is 6/off, 4/2 after which White should not redouble.

Correct play is 6/3, 2/1 after which White should redouble. Wrong play is 6/3, 5/4 after which White should not redouble.

Correct play is 6/3, 5/1 after which White should redouble. Wrong play is 6/3, 6/2 after which White should not redouble.

Here is my limited understanding which I am sure can be improved.

When Black has made the correct play, White should redouble because there is a low probability (i) that White could have a later more efficient redouble and/or (ii) that Black, if redoubled now, could have a later efficient redouble to 8.

When Black has made the wrong play, White should not redouble because there is then a sufficiently high probability (i) that White could have a later more efficient redouble and/or (ii) that Black, if redoubled now, could have a later efficient redouble to 8.

Congratulations to Jeroen for creating a program to search for these plays. (I have of course verified that XG Roller++ is in agreement.)

Messages In This Thread

 

Post Response

Your Name:
Your E-Mail Address:
Subject:
Message:

If necessary, enter your password below:

Password:

 

 

[ View Thread ] [ Post Response ] [ Return to Index ] [ Read Prev Msg ] [ Read Next Msg ]

BGonline.org Forums is maintained by Stick with WebBBS 5.12.