Introduction: Heads Up No Limit Hold’em Sit-n-Go’s

This is post #7 in an ongoing series of articles about my work as a poker bot developer.

There are two ways to play poker: cash games and tournaments.

In cash games, your chips are worth dollar amounts. When you bet $20, you actually risk $20. You can usually start and stop playing at any point and when you’re done, you trade your remaining chips in for their cash value.

In tournament poker, chips don’t represent dollar amounts. This is usually the type of poker you see airing on ESPN and the Travel Channel. You pay money to join the tournament, get a certain number of chips, and then play until you lose all your chips or win everyone else’s. You get paid based on how many people are left when you lose all your chips and that amount varies based on the structure of the tournament.

Sit-n-Go’s are basically fast tournaments. They’re specially designed not to last very long.

There are many types of Sit-n-Go’s depending on what type of poker you enjoy playing: 2, 4, 8, 9, 27, 180 people, Limit, Pot Limit, No Limit, Omaha, Stud, Razz, HORSE, etc.

The poker bot I designed was for Pokerstar’s Low Stakes Turbo No Limit Hold’em Heads Up Sit-n-Go’s, or, simply, HUSNGs.

That means:

  • PokerStars – One of the leading online poker sites
  • Low Stakes – The bot is profitable at the $2 + $0.20, $6 + $0.25, and $11 + $0.50 levels
  • Turbo – The blinds increase every 5 minutes instead of the normal 10
  • No Limit – You can bet your entire stack at any point
  • Hold’em – Two holecards, five community cards (flop, turn, and river).
  • Heads Up – You and one other opponent
  • Sit-n-Go’s – They usually last about 15 minutes.

HUSNGs were my specialty (I’ve played about 130K hands) and what I knew the most about, which is why I chose them for the bot.

To join a HUSNG, you pay a buyin and a rake. $6 + $0.25 means that the buyin is $6 and that you also have to pay $0.25 to PokerStars in order to play. That’s how they make their money. If you win the tournament, you win both buyins ($12) for a net profit of $12 – $6 – $0.25 = $5.75. If you lose, your opponent gets your buyin, so you’re out $6.25.

When the HUSNG starts you get 1500 chips and the blinds are 10/20 (the players alternate posting 10 chips and 20 chips before the cards are dealt). Five minutes later they jump to 15/30, then five minutes later 25/50, 50/100, 75/150, 100/200, and so on. Most games end before the blinds reach 75/150.

Here’s what it looks like:

With that out of the way, we can start to discuss the theory behind the poker bot’s decision making algorithms.

More to follow…

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s