Arimaa Forum - Print Page


    
      
        Arimaa Forum
        (http://arimaa.com/arimaa/forum/cgi/YaBB.cgi)
      

        Arimaa >> Bot Development >> Speedy/bomb weaknesses
        
(Message started by: fotland on Mar 2^nd, 2004, 11:37pm)

Title: Speedy/bomb weaknesses
Post by fotland on Mar 2^nd, 2004, 11:37pm

It looks like speedy often wants to put its horse on the enemy trap and have it stuck there. This must be a bug in the evaluation. Do you agree that it seems to seek out that position? I've seen it in several games.

Title: Re: Speedy/bomb weaknesses
Post by omar on Mar 4^th, 2004, 9:03pm

Im not sure that it seeks out such positions, because if it gets a chance it will try to frame the opponents pieces on a trap square as well. So it seems to know that's getting framed is not a good thing.

Omar

Title: Re: Speedy/bomb weaknesses
Post by 99of9 on Mar 5^th, 2004, 6:49pm

I agree that speedy almost seems to allow you to frame minor pieces.

I also think speedy is too cavalier with its elephant - twice now I have jammed it into positions it could never get out of. This doesn't just lose a piece, it loses the whole game, so is very important to avoid.

Finally I think speedy is too willing to move rabbits off the backline. One of the commonest ways to beat speedy is to get the elephant stuck defending a framed piece, then wait for speedy's rabbits to come and get killed. In this circumstance speedy should keep its rabbits back and activate the camel instead. (or flood the elephants with rabbits to trap them both... but that's a whole different story).

Title: Re: Speedy/bomb weaknesses
Post by fotland on Mar 6^th, 2004, 12:44am

When a piece is framed, it looks at the strength of the pieces doing the framing, so the value could be positive or negative. If elephant, camel, and horse are framing a horse with an elephant defending, the framer is using a camel to do the frame, so this is bad for the framer. But now I think this is not right, since after the frame, the framing pieces can be exchanged for better ones.

Title: Re: Speedy/bomb weaknesses
Post by 99of9 on Mar 25^th, 2004, 7:42am

on 03/05/04 at 18:49:07, 99of9 wrote:

I also think speedy is too cavalier with its elephant - twice now I have jammed it into positions it could never get out of. This doesn't just lose a piece, it loses the whole game, so is very important to avoid.

Looks like the others have figured out how to REALLY exploit this and win every game this way.

It's an interesting problem for bots in general actually - whether to accept the offer of a free piece to have your elephant locked away. It's worth it if there's a reasonable chance of unlocking the elephant with your other pieces, but otherwise, you shouldn't even accept a camel offer.