Comments on: Backgammon, Stakes, AI Wed, 10 Sep 2014 18:53:13 +0000 hourly 1 By: Anonymous Thu, 26 Feb 2009 14:25:00 +0000 The fun of backgammon, I think, is that when you are sure to win, you are forced to open, and your opponent lands right on top. The game is reversed. Good players know how to use their defence for possible exploitation. I think this makes the game addictive, especially when you are playing face to face with someone, and see his sad face after throwing a 1-6 to land on his guy waiting at 7.

I use AI to improve my game, but in order to win against humans, just AI is not enough.

And I like the saying “luck is a residue of design”


By: Darius Kazemi Mon, 15 Oct 2007 13:20:00 +0000 Hi Mai,

I play backgammon exclusively on my Palm phone. As a result I only play against AI.

When I’m at my computer I almost never play backgammon because I have thousands (literally) of other games I could be playing. However, I will give online backgammon a shot, just to see how I like it.

By: Mai Mon, 15 Oct 2007 08:41:00 +0000 Try playing against real people, Darius. There’re loads of good online multi-player sites these days. Granted, some of the ‘real’ people are in fact bots – but check out the forums and you’ll see real players ratting on them, so you’ll know which games to avoid. Here’s some good multi-player Backgammon games you might enjoy

Mai :-)

By: Darius Kazemi Tue, 29 Aug 2006 12:51:00 +0000 On your first point, I guess I forgot to mention that in the version of Backgammon I play (for PalmOS), you don’t play to a number of points. You play FOREVER, accumulating points. Which is weird. Right now the score is AI: 2640, Darius: 1958.

Second point: you’re right, a suboptimal AI would be more fun. This version of Backgammon has an optimal AI.

Third: I actually think endgame in Backgammon is really fun. But that’s because I’ve taken advanced probabilistic signals courses. I could write another essay about this (and I probably will), but I have a strategy for the endgame of backgammon based on laying out your pieces in a modified probability distribution function. I also think endgame is really visceral, but that’s because I always abstract everything while playing–so endgame for backgammon might as well be endgame for an RTS.

And maybe it says something about my RTS play style that the endgame is always a forgone conclusion by the time I send my troops in. (I’m a builder.)

Thanks for the hefty response. I was afraid that nobody would want to talk about Backgammon!

By: Ian Schreiber Tue, 29 Aug 2006 03:46:00 +0000 Wow, Darius, it’s extremely rare that I disagree with you so much.

First: Knowing when to double (and accept/reject) isn’t the cut-and-dried probability equation that you make it out to be; there are other factors that extend beyond how “ahead” you are in the current game. For example, suppose I have 4 points and you have 6, and we’re playing to 10. I’m ever-so-slightly ahead; do I double? Not a chance; you instantly redouble, and now a slightly fortunate roll on your part wins you the match. So I might have to be “more” ahead in a case like this, than if we were just starting out. As another example, suppose I’ve decided that you’re simply a more skillful player than I am, hands-down. Then I should be MUCH more liberal in when to double (and accept your double), because I’m gonna need some extra luck on my side to counter your extra skill anyway, so I’m better off reducing the number of games in the match so that luck plays a greater role in the outcome. Note that deciding “how much better” a player you are than me is something that can’t be done with math, unless we’ve played each other a LOT :)
And of course if there’s a possibility of a gammon or backgammon, doubling may actually benefit your opponent by reducing the cost of their loss…

Second: You say that an optimal AI is no fun to play against, which is true, but then you add a corollary that therefore playing against a computer is Not Fun. Who said the AI has to play optimally? An optimal AI for “Pong” isn’t fun either, but a suboptimal AI that can be outplayed is certainly possible to build. What if your backgammon AI had certain probability thresholds, where it won’t double unless it’s ahead by a fair enough margin that you don’t feel it’s premature? What if its doubling/accepting/rejecting decision has a random element built in, so that there’s a chance it will double when it isn’t quite as ahead as it should be, and now you (the human) have to decide if the CPU is “bluffing” or not?

Third: comparing Backgammon to an RTS is a bit of a stretch. In an RTS, that final clash of units is visceral specifically because of, well, the viscera. Blood flying everywhere, death, carnage, all in one massive winner-take-all battle. Now compare with the endgame of Backgammon, where after it’s a running game and there’s no more interactivity, it’s mostly a tedious chore to roll your dice and bear off — there are few interesting decisions at this point, and if one player is far ahead it’s an act of mercy for the winner to double, allow a concession, and get past the boring endgame into the interesting start of the next game. A better comparison would be if you’re allowed to concede in that RTS *after* you lose all your forces in that big battle, so your opponent doesn’t have to go through the motions of mopping up what’s left.