NeuroGammon

[Scott.Fahlman@B.GP.CS.CMU.EDU]

    1. Can we make the claim that we are doing better that AI (chess) efforts,
       mentioned as one of the AI conerstone results in the Oct88(?) AI magazine
       (AAAI), since it is a different game. I recall Tesauro mentioning in NIPS
       that backgammon was heavily pattern based, as opposed to chess.
    2. Is anybody aware of results for NN in chess or AI in backgammon?

I agree that comparing neural-net backgammon to conventional AI chess
programs would be pretty meaningless.  But there are a number of
conventional AI programs that play backgammon.  The most famous of these,
Hans Berliner's program, once beat the human world champion in backgammon.
It had some lucky rolls, but then a good backgammon player willattempt to
keep the board in a state where most rolls are "lucky" and where "unlucky"
rolls can't do too much harm.  Unfortunately, Berliner's program wasn't in
the tournament that NeuroGammon won, but several other AI-type programs
were there.  Maybe Gerry can give us some estimate of whether these
programs were in the same class as Berliner's program.

    3. Could AI do better in a heavily pattern based game?

Depends what you mean by "pattern-based".  Backgammon is all patterns, but
it also has the interesting feature of uncertainty; chess and Go are
deterministic.  Chess can be played using a lot of knowledge and a little
search or vice-versa.  People tend to use a lot of knowledge, but the
current trend in computer chess is toward very search-intensive chess
machines that have little in common with other areas of AI: no complex
knowledge representations, no symbolic learning, etc.  If this trend
continues, it will mean that chess is no longer a good problem for driving
progress in AI, though it will help to stimulate the development of
parallel search engines.

I think that Go is going to turn out to be the really interesting game for
neural nets to tackle, since the search space is more intractable than the
search space in chess, and since patterns of pieces influence the choice of
move in subtle ways that master players cannot easily explain.  There is
still an important element of serial search, however -- I don't think even
the masters claim to select every move by "feel" alone.

    4. Does Tesauro plans some form of rule estimate to compare game complexity?

The size of the rule set has very little to do with the strategic
complexity of a game.  Monopoly has a more complex rule set than Go, but
is MUCH easier to play well.

    6. how can one better compare this apples and oranges results?

Try not to.

-- Scott