Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Gunnar Farnebäck
Peter Drake wrote: On Aug 1, 2008, at 8:08 AM, Mark Boon wrote: The neighbours of the last move come in the picture because usually it's only the last stone played that can be escaping a ladder and it's the neighbours of the last move that could have been put into atari. Nothing to do with

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Jason House
On Aug 2, 2008, at 4:31 AM, Gunnar Farnebäck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves in the playouts, regardless whether it's a ladder or not. This would result in those stones being captured in most simulations. What method do people use for finding capture

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Álvaro Begué
On Sat, Aug 2, 2008 at 9:43 AM, Jason House [EMAIL PROTECTED] wrote: On Aug 2, 2008, at 4:31 AM, Gunnar Farnebäck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves in the playouts, regardless whether it's a ladder or not. This would result in those stones being captured

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Peter Drake
Depending on your implementation, it may be faster to re-derive the liberty list when you need it. For example, if your playout move suggester only suggests capturing the last stone played, you don't need to do all of the work to update liberty counts for any other chains. Thanks a lot

RE: [computer-go] Ladders and UCT again

2008-08-02 Thread David Fotland
I keep liberty counts. David -Original Message- From: [EMAIL PROTECTED] [mailto:computer-go- [EMAIL PROTECTED] On Behalf Of Jason House Sent: Saturday, August 02, 2008 6:43 AM To: computer-go Subject: Re: [computer-go] Ladders and UCT again On Aug 2, 2008, at 4:31 AM, Gunnar

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Hideki Kato
: [computer-go] Ladders and UCT again On Aug 2, 2008, at 4:31 AM, Gunnar Farnebck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves in the playouts, regardless whether it's a ladder or not. This would result in those stones being captured in most simulations. What method

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Łukasz Lew
On Sat, Aug 2, 2008 at 16:06, Álvaro Begué [EMAIL PROTECTED] wrote: On Sat, Aug 2, 2008 at 9:43 AM, Jason House [EMAIL PROTECTED] wrote: On Aug 2, 2008, at 4:31 AM, Gunnar Farnebäck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves in the playouts, regardless whether

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Łukasz Lew
- [EMAIL PROTECTED] On Behalf Of Jason House Sent: Saturday, August 02, 2008 6:43 AM To: computer-go Subject: Re: [computer-go] Ladders and UCT again On Aug 2, 2008, at 4:31 AM, Gunnar Farneb ck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves in the playouts

RE: [computer-go] Ladders and UCT again

2008-08-02 Thread David Fotland
stronger. All of these numbers are for 9x9. David -Original Message- From: [EMAIL PROTECTED] [mailto:computer-go- [EMAIL PROTECTED] On Behalf Of Lukasz Lew Sent: Saturday, August 02, 2008 3:50 PM To: computer-go Subject: Re: [computer-go] Ladders and UCT again Can you describe your

Re: [computer-go] Ladders and UCT again

2008-08-02 Thread Hideki Kato
] [mailto:computer-go- [EMAIL PROTECTED] On Behalf Of Jason House Sent: Saturday, August 02, 2008 6:43 AM To: computer-go Subject: Re: [computer-go] Ladders and UCT again On Aug 2, 2008, at 4:31 AM, Gunnar Farneb ck [EMAIL PROTECTED] wrote: It's often a good idea to bias capturing moves

Re: [computer-go] Ladders and UCT again

2008-08-01 Thread Mark Boon
On 31-jul-08, at 21:00, Peter Drake wrote: What you're missing (or so it seems to me) is that it's not to prevent from running a ladder that is caught. Really? My motivation has been to prevent my program from embarrassingly running in just those situations. Is there something other

Re: [computer-go] Ladders and UCT again

2008-08-01 Thread Peter Drake
On Aug 1, 2008, at 8:08 AM, Mark Boon wrote: The neighbours of the last move come in the picture because usually it's only the last stone played that can be escaping a ladder and it's the neighbours of the last move that could have been put into atari. Nothing to do with the additional

Re: [computer-go] Ladders and UCT again

2008-08-01 Thread terry mcintyre
From: Peter Drake [EMAIL PROTECTED] It seems too expensive to search every point on the board for ladders. What to do? Perhaps it would be worthwhile to preserve state from board to board - there are unlikely to be more than 2 or 3 ladders on any given board. When a stone is played,

Re: [computer-go] Ladders and UCT again

2008-08-01 Thread Mark Boon
On 1-aug-08, at 14:15, Peter Drake wrote: On Aug 1, 2008, at 8:08 AM, Mark Boon wrote: The neighbours of the last move come in the picture because usually it's only the last stone played that can be escaping a ladder and it's the neighbours of the last move that could have been put into

Re: [computer-go] Ladders and UCT again

2008-08-01 Thread John Fan
Ladder read should be helpful in the open space. But when the surrounding area is not full of space, the ladder play could hurt the eyes. for example below in the corner. b is better than a. By ladder reading, it would play at a, and the defender answer at b, leaves the attacker no eye in the

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread Jason House
On Thu, 2008-07-31 at 15:50 -0700, Peter Drake wrote: I know we had this conversation recently, but I just can't seem to get my head around writing a ladder reader. What, exactly, does the ladder reader do? Our approach was to read out ladders involving the last stone played. In the

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread Mark Boon
On 31-jul-08, at 19:50, Peter Drake wrote: I know we had this conversation recently, but I just can't seem to get my head around writing a ladder reader. What, exactly, does the ladder reader do? Our approach was to read out ladders involving the last stone played. In the playout

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread Don Dailey
I did a ladder reader once. Basically it's an alpha beta search where you focus on one group only, and that group has limited liberties. If it's strictly ladder reading, you only consider attacks that reduce the liberty count of a specific string to 1 (atari moves in other words) and defenses

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread Peter Drake
On Jul 31, 2008, at 4:24 PM, Mark Boon wrote: On 31-jul-08, at 19:50, Peter Drake wrote: I know we had this conversation recently, but I just can't seem to get my head around writing a ladder reader. What, exactly, does the ladder reader do? Our approach was to read out ladders

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread terry mcintyre
From: Peter Drake [EMAIL PROTECTED] Our approach was to read out ladders involving the last stone played. In the playout (beyond the tree), if the attacker can capture by continuing a ladder, the attacker plays that move. If the defender can escape by running, the defender plays that move.

Re: [computer-go] Ladders and UCT again

2008-07-31 Thread Peter Drake
Okay, let me see if I can sum this all up. Let 2, capture, attacker stand for defending chain has 2 liberties, it will be captured if the ladder is played out, and it is the attacker's turn. Use the following rules to suggest moves: 1, capture, defender = defender plays ladder breaker,