Re: [Bug-gnubg] Neural network symmetry question

2011-12-16 Thread Ian Shaw
Øystein Schønning-Johansen wrote: Sent: 12 December 2011 20:59 So, we don't care about the exactness of the absolute evaluation, we care about the relative evaluation between the moves (or resulting positions after each move). That is what makes it select good moves! This strategy was

Re: [Bug-gnubg] Neural network symmetry question

2011-12-16 Thread Thomas A. Moulton
If gnubg could estimate the opponents rating based upon error rate then it could be more aggressive on a redouble since the other player is likely to make errors to modify the cube decision. This may have NOTHING to do with what your're talking about right now... :) Tom On 12/16/2011 06:43

Re: [Bug-gnubg] Neural network symmetry question

2011-12-16 Thread Ian Shaw
thought about this angle. n Ian From: Thomas A. Moulton [mailto:t...@moulton.us] Sent: 16 December 2011 12:00 To: Ian Shaw Cc: Øystein Schønning-Johansen; Mark Higgins; Frank Berger; bug-gnubg@gnu.org Subject: Re: [Bug-gnubg] Neural network symmetry question If gnubg could estimate

Re: [Bug-gnubg] Neural network symmetry question

2011-12-16 Thread Joseph Heled
Subject: Re: [Bug-gnubg] Neural network symmetry question If gnubg could estimate the opponents rating based upon error rate then it could be more aggressive on a redouble since the other player is likely to make errors to modify the cube decision. This may have NOTHING to do with what

Re: [Bug-gnubg] Neural network symmetry question

2011-12-12 Thread Mark Higgins
I ran my test out to 400k runs and the symmetric network starting drifting down, with the normal one edging it out in head to head competitions. But the real evidence against it came from looking at probability estimates from a couple benchmark positions: one where white is almost certainly

Re: [Bug-gnubg] Neural network symmetry question

2011-12-12 Thread Øystein Schønning-Johansen
On Mon, Dec 12, 2011 at 9:11 PM, Mark Higgins migg...@gmail.com wrote: I assume this is what the gnubg benchmark stuff is about btw? Comparing probability estimates in a bunch of benchmark board positions against rolled-out probabilities? How do you condense the many different cases into a

Re: [Bug-gnubg] Neural network symmetry question

2011-12-11 Thread Mark Higgins
I tried a little experiment on this: a 10-hidden-node network with a single probability-of-win output, but two setups. The first doesn't have a whose turn is it input and doesn't add any symmetry constraints. The second has the extra inputs for the turn and makes the symmetry constraint I

Re: [Bug-gnubg] Neural network symmetry question

2011-12-11 Thread Joseph Heled
My experience tells me that 100,000 trials may not be sufficient. With today's computing power it should be easy to do at least a couple of millions. -Joseph On 12 December 2011 11:22, Mark Higgins migg...@gmail.com wrote: I tried a little experiment on this: a 10-hidden-node network with a

Re: [Bug-gnubg] Neural network symmetry question

2011-12-11 Thread Mark Higgins
Thx - I'll run it longer and with more hidden nodes and see what happens. On Dec 11, 2011, at 5:44 PM, Joseph Heled jhe...@gmail.com wrote: My experience tells me that 100,000 trials may not be sufficient. With today's computing power it should be easy to do at least a couple of

Re: [Bug-gnubg] Neural network symmetry question

2011-12-10 Thread Mark Higgins
You have an input that represents whose turn it is (one input for white, one for black, value one if that player is on turn and zero otherwise). I think that's in the original Tesauro setup isn't it? On Dec 10, 2011, at 1:10 AM, Joseph Heled jhe...@gmail.com wrote: Well, I am not sure how

[Bug-gnubg] Neural network symmetry question

2011-12-10 Thread Frank Berger
Hi Mark, If I take a given board and translate the position into the inputs and then evaluate the network, it gives me a probability of win. If I then flip the board's perspective (ie white vs black) and do the same, I get another probability of win. Those two probabilities should sum to

Re: [Bug-gnubg] Neural network symmetry question

2011-12-10 Thread Mark Higgins
Thx! Makes sense. Though I wonder if adding back in the whose move is it input and reducing the hidden-output weights by half ends up as a net benefit for training. Maybe I'll test it out. On Dec 10, 2011, at 2:06 PM, Frank Berger fr...@bgblitz.com wrote: Hi Mark, If I take a given

[Bug-gnubg] Neural network symmetry question

2011-12-09 Thread Mark Higgins
I've been playing around a bit with neural networks for backgammon and found something interesting, and want to see whether this is already part of gnubg. Assume a Tesauro-style network with the usual inputs, and some number of hidden nodes. And for simplicity, just one output representing the

Re: [Bug-gnubg] Neural network symmetry question

2011-12-09 Thread Joseph Heled
Well, I am not sure how you flip the position, since it matters who is on the move. -Joseph On 10 December 2011 16:17, Mark Higgins migg...@gmail.com wrote: I've been playing around a bit with neural networks for backgammon and found something interesting, and want to see whether this is