

Computer Faces Poker Pros in No-Limit Texas Hold’Em Competition - empressplay
https://www.cmu.edu/news/stories/archives/2015/april/computer-faces-poker-pros.html

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kyberias
The scientist behind the AI, Tuomas Sandholm, has a nice 115 page resume:
[http://www.cs.cmu.edu/~sandholm/cv.pdf](http://www.cs.cmu.edu/~sandholm/cv.pdf)

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hop
That's crazy.

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kriro
The most important piece of information seems to be missing. What's the stack
depth? In the AAAI HUNL competition it's 200 big blinds which is significantly
harder to be good at than 100 big blinds which is the standard for online HU
play.

I think you can actually build a fairly competitive HU bot for 100bb games
with very simple means (rules based with a bit of statistics thrown in, no
opponent modelling or advanced features or learning). At 200bb it's a lot
harder and researchers that approach it from an "understanding of the game"
POV rather than a "pure computation" POV have a tougher time.

Edit: I only know Doug (aka WCGRider). Wish they would play against Ike
Haxton, jungleman12, sauce123, Galfond or Durrr

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learnstats2
>it's 200 big blinds which is significantly harder to be good at than 100 big
blinds which is the standard for online HU play.

I'm quite surprised by this!

100bb has higher variance and therefore more luck, where 200bb has lower
variance

So, I would say the 200bb tournament rewards skilled (human) players more
effectively. As a skilled player, I would seek out the 200bb tournaments.

My immediate thought would be that a computer player would be rewarded better
in the 200bb tournament.

But, even in the 200bb situation, players will have to play short stacked some
of the time. Perhaps the difficulty for bots is the requirement of changeable
modes here?

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grwgreg
They're not playing tournament style. The blinds are fixed and I think the
players stacks are reset before each hand.

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fsk
I don't see where they got 10^161 as the number of situations in no-limit. You
can bet ANY amount, making it potentially unlimited. You also have to consider
the ratio of the size of your stack to the size of the blinds, which means the
number of situations is unlimited (arbitrarily deep stacks).

I.e., if the blinds are $1-$2, you follow a completely different strategy when
you have $10 as when you have $100 or $10000.

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learnstats2
> You can bet ANY amount, making it potentially unlimited.

Not really.

The minimum bet size is fixed by the blinds/antes.

The maximum bet is fixed by the total number of chips in the tournament (or
that the player holds).

The bet amounts are limited by the size of the smallest chip - in bricks and
mortar tournaments tournament managers will 'chip up' the small chips whenever
it becomes sensible to do so. In digital tournaments the smallest chip might
remain at $0.01, but it still exists.

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fsk
Suppose again the blinds are $1-$2 and the stack is $10000.

I can bet $2, $4, $6, $8, $10, $12, $14, any amount up to $10000. Each of
those is now a separate game tree. A couple of bets, and now we're way past
10^161.

It may never be optimal for me to bet $132, but a perfect computer player
should be prepared for that bet.

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cardprophet
While you are theoretically correct that the game tree is massive, the
difference in tree between betting 1bb vs 2bb in a 50bb pot is marginal; the
algorithm they use considers an abstraction of the game.

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fsk
So they're just doing an approximate game tree.

Small differences in bet size can matter, because professional players will
sometimes try to give you the pot odds to make a bad call.

